AUTO START STOP (DIAGNOSTICS)
AS(diag)

AUTO START STOP (DIAGNOSTICS) > Basic Diagnostic Procedure
PROCEDURE

1. PERFORM CUSTOMER INTERVIEW.

Ask the customer when and how the trouble occurred using the interview check list. AUTO START STOP (DIAGNOSTICS)>Check List for Interview

Did you interview the customer?

2

Perform the interview, and 2

2. CHECK Auto Start Stop OFF INDICATOR.

Does the Auto Start Stop warning light (yellow) illuminate?

3

Check the combination meter. COMBINATION METER (DIAGNOSTICS)>Active Test

3. CHECK SUBARU SELECT MONITOR COMMUNICATION.

Check for communication with TCM.

If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

Is communication possible?

4

Check the communication circuit. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

4. CHECK DTC.

Read the DTC of [Auto Start Stop] using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. After diagnosis, 5

Perform diagnosis according to the procedures in the diagnostics with phenomenon. AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon

5. PERFORM DIAGNOSIS.
1.

Using the Subaru Select Monitor, perform the clear memory of [Auto Start Stop]. COMMON(diag)>Clear memory

2.

Execute the inspection mode. AUTO START STOP (DIAGNOSTICS)>Inspection Mode

3.

Read the DTC of [Auto Start Stop] using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Finish the diagnosis.

AUTO START STOP (DIAGNOSTICS) > Check List for Interview
CHECK

- Inspect the following items regarding the vehicle’s state.

- Print out below for use.

Auto Start Stop Check List for Interview | Date of Vehicle Bring-in   Year   Month   Date
Customer’s name | Registration No. | Initial year of registration Year   Month  Date
Vehicle model | Frame number
Interviewer | Inspector | Engine type | Odometer reading
Customer specified content • • •
Date when problem occurred | Year   Month  Date | Frequency of trouble occurrence | Always occurs Sometimes occurs (   times per day,    times per month)
Condition of trouble occurrence | Weather Fine Cloudy Rainy Snowy Others (             )
Temperature °C (°F)
a) Warning lights or indicators illuminate or blink. : Yes / No
Auto Start Stop indicator light Auto Start Stop OFF indicator light Auto Start Stop deactivation indicator light Fuel level warning light Charge warning light Engine coolant temperature warning light Oil pressure warning light Malfunction indicator light ATF temperature warning light or Sport indicator light Driver’s control center differential indicator light ABS warning light VDC warning light Cruise indicator light SI-CRUISE warning light Immobilizer indicator light STEERING warning light Electronic parking brake warning light Glow indicator light Sedimenter warning light Other:
b) Battery
Specified battery is equipped: Yes / No Battery voltage:
c) Battery replacement: Yes / No
Date of replacement: Travel distance at replacement:
d) Starter
Number of times for starting: Starter has ever been replaced: Yes / No
e) Installing of other parts except genuine parts to the equipped electrical parts: Yes / No
Equipped electrical parts Audio (including non-genuine parts): amplifier, speaker (woofer), others (                ) ETC
Part name: Installation location (power inlet location) :          (                ) :          (                ) :          (                ) :          (                ) :          (                )
f) Troubles occurred
Engine does not stop. The engine stop period is short. Buzzer sounds (intermittently) while the engine stops. Buzzer sounds (continuously) while the engine stops. Engine does not restart after it stops. When restarting, the audio/navigation system is reset (initialized). When restarting, the combination meter and MFD blink. Electrical equipment such as automatic air conditioner, audio, navigation system, or combination meter does not operate. Other:

AUTO START STOP (DIAGNOSTICS) > General Description
CAUTION
1. AIRBAG SYSTEM

- Do not use the electrical test equipment on the airbag system wiring harnesses and connector circuits.

- Be careful not to damage the airbag system wiring harness.

2. CONTROL MODULE
1.

The TCM connector is waterproof. When measuring the TCM connector terminal voltage, or the resistance between the terminals, use the check board.

2.

When measuring the voltage or resistance of individual sensors, use a tapered pin with a diameter of 0.6 mm (0.024 in) or less and touch it to the tip of terminal. Never insert the tapered pin into the terminal because it deforms inside which may lead to malfunction.

If a taper pin or the like has been inserted into the connector terminal, replace the connector.

AUTO START STOP (DIAGNOSTICS) > General Description
INSPECTION
1. BASIC INSPECTION

Before performing diagnosis, check the following items which might affect the problems related to Auto Start Stop.

1.

Check the battery.

2.

Check the relay and fuse condition.

3.

Check the connecting condition of harness and connector.

AUTO START STOP (DIAGNOSTICS) > General Description
PREPARATION TOOL
1. SPECIAL TOOL

ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
| — | SUBARU SELECT MONITOR 4 | Used for setting of each function and troubleshooting for electrical system. For detailed operation procedures of Subaru Select Monitor 4, refer to “Help” of application.
| 18460AA040 | CHECK BOARD | Used for measuring voltage and resistance of TCM terminals.
| 18460AA180 | CHECK BOARD | Used for measuring voltage and resistance of ECM terminals.

2. GENERAL TOOL

TOOL NAME | REMARKS
Circuit tester | Used for measuring resistance, voltage and current.
Oscilloscope | Used for measuring the sensor.
DST-i | Used together with Subaru Select Monitor 4.

AUTO START STOP (DIAGNOSTICS) > General Description
SYSTEM BLOCK DIAGRAM
AUTO START STOP (DIAGNOSTICS) > Electrical Component Location
LOCATION

(1) | TCM | (2) | ECM | (3) | Front hood lock ASSY (with integrated hood switch)

(1) | DC/DC converter 1 | (2) | DC/DC converter 2 (with audio amplifier) | (3) | Auto Start Stop cancel switch

(1) | Electric oil pump | (2) | Inhibitor switch |  |

(1) | Electric oil pump relay | (2) | Starter relay | (3) | Starter cut relay

AUTO START STOP (DIAGNOSTICS) > Control Module I/O Signal
ELECTRICAL SPECIFICATION

Refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Transmission Control Module (TCM) I/O Signal

AUTO START STOP (DIAGNOSTICS) > Control Module I/O Signal
WAVEFORM

Input/output name | Measuring condition | Waveform
Electric oil pump signal Operation status signal Operation command signal The percentage is indicated as a duty ratio when the voltage level is low. | When stopping Operation status signal (1): 30% Operation command signal (2): 10% |
When turning Operation status signal (3): 50% Operation command signal (4): 65% |

AUTO START STOP (DIAGNOSTICS) > Inspection Mode
PROCEDURE

It is possible to diagnose the DTC by performing the indicated inspection mode. After correcting the DTC, perform the inspection mode and make sure that the function is resumed correctly and the DTC is recorded.

1. INSPECTION MODE

DTC | Item | Number of driving cycles on the detecting condition | Condition
P0512 | STARTER (SWITCH) REQUEST CIRCUIT | 3 | —
P1518 | STARTER SWITCH CIRCUIT LOW | 3 | —
P1567 | AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT LOW | 5 | —
P1568 | AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT HIGH | 10 | —
P1580 | STARTER RELAY DIAGNOSIS CIRCUIT | 2 | —
P1615 | STARTER OPERATION NUMBER OF TIMES EXCESS | 1 | —
P161D | ELECTRIC FLUID PUMP (CVT) RELAY CIRCUIT LOW | 1 | —
P1625 | AUTO START REQUEST CIRCUIT LOW | 3 | —
P1626 | AUTO START REQUEST CIRCUIT HIGH | 3 | —
P1739 | ELECTRIC FLUID PUMP (CVT) DRIVE CIRCUIT | 3 | —
P173A | ELECTRIC FLUID PUMP (CVT) STATUS SIGNAL | 3 | —
P173B | ELECTRIC FLUID PUMP (CVT) PERFORMANCE | 3 | —
P173C | ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT LOW | 3 | —
P173D | ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT HIGH | 3 | —
P173E | ELECTRIC FLUID PUMP (CVT) INPUT VOLTAGE | 3 | —
P1A15 | DC/DC CONVERTER 1 BOOST COMMAND SIGNAL LOW | 2 | —
P1A16 | DC/DC CONVERTER 1 BOOST COMMAND SIGNAL HIGH | 2 | —
P1A17 | DC/DC CONVERTER 2 BOOST COMMAND SIGNAL LOW | 2 | —
P1A18 | DC/DC CONVERTER 2 BOOST COMMAND SIGNAL HIGH | 2 | —
P1A20 | DC/DC CONVERTER 1 BOOST PERFORMANCE | 2 | —
P1A21 | DC/DC CONVERTER 1 INPUT 1 VOLTAGE | 2 | —
P1A22 | DC/DC CONVERTER 1 INPUT 2 VOLTAGE | 2 | —
P1A23 | DC/DC CONVERTER 1 OUTPUT 1 VOLTAGE | 2 | —
P1A24 | DC/DC CONVERTER 1 OUTPUT 2 VOLTAGE | 2 | —
P1A25 | DC/DC CONVERTER 1 CIRCUIT 1 TEMPERATURE | 2 | —
P1A26 | DC/DC CONVERTER 1 CIRCUIT 2 TEMPERATURE | 2 | —
P1A27 | DC/DC CONVERTER 1 INTERNAL CIRCUIT | 2 | —
P1A28 | DC/DC CONVERTER 2 BOOST PERFORMANCE | 2 | —
P1A29 | DC/DC CONVERTER 2 INPUT 1 VOLTAGE | 2 | —
P1A2A | DC/DC CONVERTER 2 INPUT 2 VOLTAGE | 2 | —
P1A2B | DC/DC CONVERTER 2 OUTPUT 1 VOLTAGE | 2 | —
P1A2C | DC/DC CONVERTER 2 OUTPUT 2 VOLTAGE | 2 | —
P1A2D | DC/DC CONVERTER 2 CIRCUIT 1 TEMPERATURE | 2 | —
P1A2E | DC/DC CONVERTER 2 CIRCUIT 2 TEMPERATURE | 2 | —
P1A2F | DC/DC CONVERTER 2 INTERNAL CIRCUIT | 2 | —
P1C00 | BATTERY MONITOR MODULE "A" PERFORMANCE | 2 | —
P257E | Engine Hood Switch Circuit Low | 3 | —
P257F | Engine Hood Switch Circuit High | 3 | —
U0073 | CONTROL MODULE COMMUNICATION BUS OFF | 1 | —
U0100 | LOST COMMUNICATION WITH ECM/PCM "A" | 1 | —
U0122 | LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE | 1 | —
U0128 | LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE | 1 | —
U0131 | LOST COMMUNICATION WITH POWER STEERING CONTROL MODULE | 1 | —
U0140 | LOST COMMUNICATION WITH BODY CONTROL MODULE | 1 | —
U0155 | LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE | 1 | —
U0164 | LOST COMMUNICATION WITH HVAC CONTROL MODULE | 1 | —
U0401 | INVALID DATA RECEIVED FROM ECM/PCM "A" | 1 | —
U0416 | INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE | 1 | —
U0417 | INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE | 1 | —
U0420 | INVALID DATA RECEIVED FROM POWER STEERING CONTROL MODULE | 1 | —
U0422 | INVALID DATA RECEIVED FROM BODY CONTROL MODULE | 1 | —
U0423 | INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUSTER CONTROL MODULE | 1 | —
U0424 | INVALID DATA RECEIVED FROM HVAC CONTROL MODULE | 1 | —
U1604 | LOST COMMUNICATION WITH DC/DC CONVERTER MODULE 1 | 2 | —
U1712 | LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR MODULE | 2 | —

2. PREPARATION FOR THE INSPECTION MODE
1.

Check that the battery voltage is 12 V or more and fuel remains approx. half [20 — 40 L (5.3 — 10.6 US gal, 4.4 — 8.8 Imp gal)].

2.

Check that the front hood is closed.

3.

Start and warm up the engine.

4.

Using the Subaru Select Monitor, read the data of Auto Start Stop and check that [ECM Idle Stop Prohibition] and [CVT idle stop prohibition] indicate “Permit”. AUTO START STOP (DIAGNOSTICS)>Data Monitor

5.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

6.

Read the diagnostic trouble code (DTC) and check that no DTC is displayed. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis using “Diagnostic Procedure with Diagnostic Trouble Code (DTC)”. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC) After solving the DTC, repeat from step 2).

7.

Turn the ignition switch to OFF.

DIAGNOSTIC PROCEDURE:

When performing inspection mode on a public road, pay sufficient attention to the traffic condition and give the highest priority to safe driving.

1.

Turn the ignition switch to ON and wait for at least 10 seconds without starting the engine.

2.

Start the engine, and run the engine at idle for 60 seconds or more while the vehicle is at a standstill.

3.

Accelerate to 40 km/h (24.9 MPH) or more, and depress the brake pedal to stop the vehicle with the gear kept in D range.

4.

Check that the Auto Start Stop functions for at least 10 seconds.

5.

Release the brake pedal to restart.

6.

Turn the ignition switch to OFF, and wait for 10 seconds or more.

7.

If the Auto Start Stop does not function for 10 seconds or more in step 4), repeat steps 1) to 5) with the number of driving cycles described in the detection condition for each DTC. AUTO START STOP (DIAGNOSTICS)>Inspection Mode

8.

Read the diagnostic trouble code (DTC) and check the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

- If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis using “Diagnostic Procedure with Diagnostic Trouble Code (DTC)”. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC) After solving the DTC, repeat from step 1).

- When the Auto Start Stop functions for at least 10 seconds, the function recovers properly.

AUTO START STOP (DIAGNOSTICS) > Auto Start Stop Indicator
CONDITION CHECK

The illumination status of the Auto Start Stop indicator, Auto Start Stop OFF indicator and Auto Start Stop deactivation indicator is related to the vehicle status as follows.

(1) | Auto Start Stop indicator (green)/ Auto Start Stop OFF indicator (Auto Start Stop warning light) (yellow) | (2) | Auto Start Stop deactivation indicator |  |

Vehicle condition | Ignition switch ON | When Auto Start Stop operation condition is not met | During Auto Start Stop | During Auto Start Stop cancellation∗1 | Malfunction occurs during Auto Start Stop.
Auto Start Stop indicator status | Light OFF | Light OFF | ON (green) | Light OFF | Light OFF
Auto Start Stop OFF indicator status | ON (yellow) ∗2 | Light OFF | Light OFF | ON (yellow) | Blink (yellow)
Auto Start Stop deactivation indicator status | Light OFF | Light ON | Light OFF | Light OFF | Light OFF

∗1: Following conditions

- Auto Start Stop is cancelled by operating the Auto Start Stop cancel switch.

- The conditions become out of the Auto Start Stop criteria during Auto Start Stop, and the system cannot restart.

∗2: After engine is started, it goes off.

AUTO START STOP (DIAGNOSTICS) > Auto Start Stop Indicator
Auto Start Stop INDICATOR DOES NOT ILLUIMINATE OR REMAINS ON

Detecting condition:

- Defective combination meter

- CAN communication is abnormal between TCM and the combination meter.

- Malfunction or open/short circuit in harness of Auto Start Stop cancel switch

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

1. CHECK Auto Start Stop OFF INDICATOR (YELLOW).
1.

Turn the ignition switch to OFF.

2.

Check that the Auto Start Stop OFF indicator (yellow) illuminates when the ignition switch is turned to ON. AUTO START STOP (DIAGNOSTICS)>Auto Start Stop Indicator>CONDITION CHECK

Is the Auto Start Stop OFF indicator (yellow) lit?

2

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

2. CHECK Auto Start Stop OFF INDICATOR (YELLOW).
1.

Start the engine.

2.

Check that the Auto Start Stop OFF indicator (yellow) goes off. AUTO START STOP (DIAGNOSTICS)>Auto Start Stop Indicator>CONDITION CHECK

Does the Auto Start Stop OFF indicator (yellow) go off?

4

3

3. CHECK DTC.
1.

Turn the ignition switch to OFF.

2.

Start the engine.

3.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

4. CHECK Auto Start Stop OFF INDICATOR (YELLOW).
1.

Operate the Auto Start Stop cancel switch to ON/OFF with engine idling.

2.

Check that the Auto Start Stop OFF indicator (yellow) illuminates and goes off in turn every time the Auto Start Stop cancel switch is turned to ON/OFF.

Does the Auto Start Stop OFF indicator (yellow) illuminate and go off?

5

6

5. CHECK Auto Start Stop INDICATOR (GREEN).
1.

Turn off the Auto Start Stop OFF indicator by operating the Auto Start Stop cancel switch.

2.

Start the engine.

3.

Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. AUTO START STOP (DIAGNOSTICS)>Active Test

Is the Auto Start Stop indicator (green) lit?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

  In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

6. CHECK Auto Start Stop DEACTIVATION INDICATOR.
1.

Turn off the Auto Start Stop OFF indicator by operating the Auto Start Stop cancel switch.

2.

Start the engine.

Is the Auto Start Stop deactivation indicator lit?

7

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

7. CHECK Auto Start Stop DEACTIVATION INDICATOR.

Start to move the vehicle.

Does the Auto Start Stop deactivation indicator go off?

8

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

8. CHECK Auto Start Stop CANCEL SWITCH.
1.

Turn the ignition switch to OFF.

2.

Start the engine.

3.

Using the Subaru Select Monitor, read the data of [Auto Start Stop OFF Switch] when the Auto Start Stop cancel switch is operated to ON/OFF. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Does the display of [Auto Start Stop OFF Switch] change?

13

9

9. CHECK Auto Start Stop CANCEL SWITCH.

Check the Auto Start Stop cancel switch. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop OFF Switch>INSPECTION

Is the check result OK?

10

Replace the Auto Start Stop cancel switch. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop OFF Switch

10. CHECK FOR SHORT CIRCUIT TO POWER SUPPLY IN HARNESS BETWEEN Auto Start Stop CANCEL SWITCH CONNECTOR AND COMBINATION METER CONNECTOR.
1.

Disconnect the connector from Auto Start Stop cancel switch.

2.

Disconnect the connector from the combination meter.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between Auto Start Stop cancel switch connector and chassis ground.

Connector & terminal

(i236) No. 6 (+) — Chassis ground (−):

Is the voltage less than 1 V?

11

Repair or replace the harness between Auto Start Stop cancel switch connector and combination meter connector.

11. CHECK FOR SHORT CIRCUIT TO GROUND IN HARNESS BETWEEN Auto Start Stop CANCEL SWITCH CONNECTOR AND COMBINATION METER CONNECTOR.

Measure the resistance between Auto Start Stop cancel switch connector and chassis ground.

Connector & terminal

(i236) No. 6 — Chassis ground:

Is the resistance 1 MΩ or more?

12

Repair or replace the harness between Auto Start Stop cancel switch connector and combination meter connector.

12. CHECK FOR OPEN CIRCUIT IN HARNESS BETWEEN Auto Start Stop CANCEL SWITCH CONNECTOR AND COMBINATION METER CONNECTOR.

Measure the resistance between Auto Start Stop cancel switch connector and combination meter connector.

Connector & terminal

(i236) No. 6 — (i10) No. 36:

Is the resistance less than 1 Ω?

13

Repair or replace the harness between Auto Start Stop cancel switch connector and combination meter connector.

13. CHECK COMBINATION METER.

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

Is the check result OK?

14

Replace the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter

14. CHECK DTC.

Using the Subaru Select Monitor, read all DTCs. LAN SYSTEM (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is U-code displayed?

Perform the diagnosis according to the DTC. LAN SYSTEM (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Replace the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure for Subaru Select Monitor Communication
COMMUNICATION FOR INITIALIZING IMPOSSIBLE

Refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

AUTO START STOP (DIAGNOSTICS) > Data Monitor
OPERATION

- For detailed operation procedures, refer to “Common (Diagnostics)”. COMMON(diag)>Diagnostic Trouble Code (DTC)

- For details on the data monitor, refer to the list. AUTO START STOP (DIAGNOSTICS)>Data Monitor>LIST

AUTO START STOP (DIAGNOSTICS) > Data Monitor
LIST

- For detailed operation procedures, refer to “Help” of application.

- A list of the support data is shown in the following table.

- ∗1: This item will be excluded from the Auto Start Stop conditions while driving.

- ∗2: This item is in the setting value that includes hysteresis. Therefore, it may be out of the conditions depending on the situation.

- ∗3: When [Idle stop prohibition evaluation] is [OFF], [Running experience completion evaluation] is always [Not Completed].

- ∗4: Changes by gradient. (Value is obtained when on a level ground)

- ∗5: Only for model with EyeSight

Item | Content and unit of measurement | Reference value
At idling | Auto Start Stop operation condition (Idling → Auto Start Stop) | Auto Start Stop restart conditions (Auto Start Stop → Restart) | Condition for cancel (During Auto Start Stop → Engine stall)
Trip Count | Timestamp information_trip counter [Time] | — | — | — | —
Count | Timestamp information_original count identification information | Common | — | — | —
Time Count | Timestamp information_time counter [ms] | — | — | — | —
Ignition Switch(Auto Start Stop) | Ignition switch signal | ON | ON | — | —
Starter Switch | Starter switch signal | OFF | — | — | —
Stop Light Switch(Auto Start Stop) | Stop light switch signal | ON | ON | OFF | —
Auto Start Stop OFF Switch | Auto Start Stop cancel switch signal | OFF | — | ON | —
System Voltage(Auto Start Stop) | Voltage of main power supply [V] | 14.4 | 12 — 15 | Less than predetermined value | —
Audio Supply Voltage | Audio power supply voltage [V] | 14.2 | 12 — 15 | Less than predetermined value | —
Brake Booster Relative Pressure | Brake booster vacuum pressure [kPa]∗1∗2 | −70 | Less than −36 | −36 or more | —
Engine Speed(Auto Start Stop) | Engine speed [rpm]∗1∗2 | 670 | 600 — 1600 | — | —
Electric oil pump diagnosis duty cycle | Electric oil pump diagnosis duty ratio [%] | 30 | 26 — 34 | — | —
DC/DC Converter Voltage Boost Request | DC/DC converter boost command signal | OFF | — | — | —
Electric Fluid Pump Relay(Auto Start Stop) | Electric oil pump relay signal | ON | ON | — | —
Electric fluid pump indication duty(Auto Start Stop) | Electric oil pump control duty ratio [%] | 10 | — | — | —
Vehicle Speed | Vehicle speed [km/h]∗1 | 0 | 0 | — | —
DC/DC Converter 1 Status | DC/DC converter 1 operation condition | Standby | Standby | — | —
Electric oil pump status | Electric oil pump operation condition | Standby | Standby | — | —
DC/DC Converter 2 Status | DC/DC converter 2 operation condition | Standby | Standby | — | —
DC/DC Converter 1 Boost Signal Reception | DC/DC converter 1 boost signal reception status | Not yet received | — | — | —
DC/DC Converter 2 Boost Signal Reception | DC/DC converter 2 boost signal reception status | Not yet received | — | — | —
Battery Terminal Voltage | Battery power supply voltage [V] | 14.4 | 12 — 15 | Less than predetermined value | —
Battery Charge/Discharge Current | Battery charge/discharge current [A] | 5 | Predetermined value or more | — | —
Estimated Battery Temperature | Estimated electrolyte temperature [°C] | 30 | 0 — 70 | Other than 0 — 70 | —
Battery Average Inner Resistance | Battery average internal resistance [mohm] | 5.7 | — | — | —
Battery Inner Resistance in cranking | Battery internal resistance at cranking [mohm] | 4.4 | — | — | —
Communication state with Battery Sensor | Battery sensor communication status | Normal | Normal | Abnormal | —
Battery sensor performance | Battery sensor function | Normal | Normal | Abnormal | —
Engine failure | CAN received data (ECM) Engine failure | Normal | Normal | Abnormal | —
Idle Switch(Accel) | CAN received data (ECM) Idling SW (accelerator)∗1 | ON | ON | OFF | —
Coolant Temp. | CAN received data (ECM) Coolant temperature [°C]∗2 | 90 | 40 — 105 | Less than 40 | —
Atmosphere Pressure | CAN received data (ECM) Atmospheric pressure [kPa]∗2 | 102 | 72.0 or more | Less than 67.0 | —
ECM Idle Stop Prohibition | CAN received data (ECM) Auto Start Stop prohibition | ON | ON | OFF | —
ECM Charging Lamp Lighting Request | CAN received data (ECM) Charging light illumination request | No request | No request | With Request | —
Accel. ON/OFF Status for Auto Vehicle Hold | CAN received data (ECM) Idling SW (accelerator) for EPB | OFF | OFF | ON | —
Shift position information | CAN received data (TCM) Shift position information | D Range Signal | D Range Signal | R Range Signal | —
Cooperative control with EyeSight | EyeSight coordinate control status | Not Operate | — | — | —
EyeSight system failure | EyeSight system failure | Normal | — | — | —
EPB Idle stop prohibition | Electronic parking brake Auto Start Stop prohibition (VDC) | ON | ON | OFF | —
Steering Angle Sensor(Auto Start Stop) | CAN received data (VDC) Steering angle [deg]∗1∗2 | 5 | −45 — 45 | Other than −60 — 60 | —
Forward and Rearward G | CAN received data (VDC) Longitudinal G [m/s^2]∗1∗2 | 0.1 | −0.8 — 0.8 | — | —
Brake fluid pressure | CAN received data (VDC) Brake fluid pressure [MPa]∗1∗2 | 0.65 | 1.0 or more∗4 | Less than 0.7∗4 | —
Brake hold operation | CAN received data (VDC) Brake hold operation | Not during control | — | — | —
Brake hold prohibition | CAN received data (VDC) Brake hold prohibition | ON | ON | OFF | —
VDC sensor failure | CAN received data (VDC) VDC sensor normal condition | Normal | Normal | Abnormal | —
FR Brake Wheel Pressure | CAN received data (VDC) FR wheel cylinder pressure [MPa]∗2∗5 | 0.65 | 1.1 or more | Less than 1.0 | —
FL Brake Wheel Pressure | CAN received data (VDC) FL wheel cylinder pressure [MPa]∗2∗5 | 0.65 | 1.1 or more | Less than 1.0 | —
A/C Idle Stop Permission | CAN received data (ACN) Auto Start Stop operation permission | ON | ON | OFF | —
A/C System Failure | CAN received data (ACN) ACN failure | Normal | Normal | Abnormal | —
AVH Operation | CAN received data (VDC) AVH activation | Not established | — | — | —
AVH Brake Intensify Press | CAN received data (VDC) AVH brake pressure intensification | Not established | Not established | — | Established
AVH SW | CAN received data (VDC) AVH switch | OFF | — | — | —
VDC Idle Stop Prohibition | CAN received data (VDC) Auto Start Stop prohibition | ON | ON | OFF | —
Remote Control Engine Starter Start Request | CAN received data (BIU) Remote start request | no support | — | — | —
EPS idle stop prohibition | CAN received data (EPS) Auto Start Stop prohibition∗1 | ON | ON | OFF | —
EPS system failure | CAN received data (EPS) System failure | Normal | Normal | Abnormal | —
Power Rear Gate operation | CAN received data (BIU) Power rear gate status | Not Operate | Not Operate | Operate | —
Rear Defogger | CAN received data (BIU) Rear defogger | OFF | OFF | ON | —
Door SW (D Seat Side) | CAN received data (BIU) Door SW (driver’s seat) | Close | Close | Open | —
Hood SW (Hood Close Status) | CAN received data (BIU) Hood SW (closed side) | ON | ON | — | OFF
Hood SW (Hood Open Status) | CAN received data (BIU) Hood SW (open side) | OFF | OFF | — | ON
Seat Belt Buckle Switch (D Seat Side) | CAN received data (MET) Seat belt SW (driver’s seat) | ON | ON | OFF | —
Auto Start Stop operation permission evaluation | Judgment of Auto Start Stop operation permission | ON | ON | — | OFF
Key start completion evaluation | Judgment of key start completion | Completed | Completed | — | —
Auto Start Stop fault evaluation | Judgment of Auto Start Stop malfunction | Normal | Normal | Abnormal | —
Engine started evaluation | Judgment of engine start | Started | Started | — | —
Under Auto Start Stop control | Judgment of Auto Start Stop control status | Other than under control | — | — | —
Idle stop request | Auto Start Stop request | No request | — | — | —
Running experience completion evaluation | Judgment of running experience completion at a speed of 5 km/h (3 MPH) or above after starting engine∗3 | Not Completed | Completed | — | —
Idle stop evaluation | Judgment of Auto Start Stop | Other than idle stopped | — | — | —
Idle stop prohibition evaluation | Judgment of Auto Start Stop prohibition | ON | ON | OFF | —
Normal restart request evaluation | Judgment of normal restart request | No request | No request | With Request | —
Automatic restart request evaluation | Judgment of automatic restart request | No request | No request | With Request | —
Turn signal evaluation | Judgment of turn signal | OFF | OFF (when customizing is valid) | ON (when customizing is valid) | —
Cancel status | Cancel condition | ON | ON | Cancel | —
Hood open evaluation | Judgment of hood open | Close | Close | — | Open
Complete combustion evaluation | Judgment of complete combustion | Established | Established | — | —
Engine stall evaluation | Judgment of engine stall | Not established | Not established | — | —
Start Count | Number of times for starting [Time] | — | Less than 280000 | — | —
DC/DC Converter 2 Setting | Sub power supply 2 installation judgment | ON | — | — | —
Vehicle speed restart request evaluation | Judgment of vehicle speed restart request | No request | No request | With Request | —
Brake vacuum restart request evaluation | Judgment of brake vacuum pressure restart request∗1 | No request | No request | With Request | —
Battery protection restart request evaluation | Judgment of battery protection restart request | No request | No request | With Request | —
Air conditioning restart request evaluation | Judgment of air conditioner restart request | No request | No request | With Request | —
Electric accessories restart request evaluation | Judgment of electrical components restart request | No request | No request | With Request | —
Restart request judgment while stopped | Judgment of restart request while the vehicle is stopped | No request | No request | With Request | —
EPS restart request judgment | Judgment of EPS restart request∗1 | No request | No request | With Request | —
EPB restart request judgment | Judgment of electronic parking brake restart request | No request | No request | With Request | —
Low water temperature stop prohibition judgment | Judgment of stop prohibition with low water temperature | ON | ON | OFF | —
Battery high temperature prohibition judgment | Judgment of prohibition with high battery temperature | ON | ON | OFF | —
Battery low temperature prohibition judgment | Judgment of prohibition with low battery temperature | ON | ON | OFF | —
Inclination prohibition judgment | Judgment of inclination prohibition∗1 | ON | ON | OFF | —
Steering angle prohibition judgment | Judgment of steering angle prohibition∗1 | ON | ON | OFF | —
Engine rotation prohibition judgment | Judgment of engine rotation prohibition∗1 | ON | ON | OFF | —
Battery current prohibition judgment | Judgment of battery current prohibition∗1 | ON | ON | OFF | —
Voltage drop prohibition evaluation at the time of start | Judgment of prohibition with battery voltage reduction at engine start | ON | ON | OFF | —
Air-conditioning prohibition evaluation | Judgment of air conditioner prohibition | ON | ON | OFF | —
DC/DC Converter Temperature Prohibition Evaluation | DC/DC converter prohibition judgment | ON | ON | OFF | —
Prohibition judgment by the atmospheric pressure condition | Judgment of prohibition with atmospheric pressure | ON | ON | OFF | —
Restart Request | CAN received data (ECM) Restart request [%] | 0 | — | — | —
ECM Restart Request Signal State | CAN received data (ECM) Restart request signal status | OFF | — | — | —

AUTO START STOP (DIAGNOSTICS) > Freeze Frame Data
OPERATION

- For detailed operation procedures, refer to “Common (Diagnostics)”. COMMON(diag)>Diagnostic Trouble Code (DTC)

- For details on freeze frame data, refer to the list. AUTO START STOP (DIAGNOSTICS)>Freeze Frame Data>LIST

AUTO START STOP (DIAGNOSTICS) > Freeze Frame Data
LIST

Display | Contents | Unit of measure
Trip Count | Total number of ignition switch ON | Time
Count | Count | —
Time Count | Elapsed time after ignition switch is turned to ON | ms
System Voltage(Auto Start Stop) | Voltage of main power supply | V
Engine Speed(Auto Start Stop) | Engine speed | rpm
Vehicle Speed | Vehicle speed | km/h or MPH
Coolant Temp. | CAN received data (ECM) water temperature | Celsius or Fahrenheit
Idle stop request | Auto Start Stop request | —
Idle stop evaluation | Judgment of Auto Start Stop | —

AUTO START STOP (DIAGNOSTICS) > Active Test
OPERATION
1.

On [Start] screen, select [Diagnosis].

2.

On [Select Vehicle] screen, input the target vehicle information and select [Confirmed].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission Control System].

5.

On [Select Function] screen, select [Active Test].

For detailed operation procedures, refer to “Help” of application.

AUTO START STOP (DIAGNOSTICS) > Active Test
LIST

- Before performing the active test for Auto Start Stop, execution conditions listed below must be met in each item.

- ∗: The restart conditions after stopping the engine are the same as that of “Auto Start Stop restart conditions”. AUTO START STOP (DIAGNOSTICS)>Data Monitor>LIST

Items | Contents | Execution condition
Electric oil pump control (Relay ON/OFF drive) | ON/OFF of the electric oil pump relay (Auto Start Stop) can be set. | “Common execution condition” established Electric oil pump diagnosis is normal
Electric oil pump control (Pump ON/OFF drive) | Command duty of the electric oil pump (Auto Start Stop) can be set to 10 → 65% (for 120 seconds). | “Common execution condition” established The value of [Coolant Temp.] is 80°C (176°F) or more CAN communication is normal
Sub power supply control (ON/OFF Dr.) | DC/DC converter can be set to ON (2 seconds). | “Common execution condition” established
Engine stop control∗ | Auto Start Stop can be performed without driving the vehicle. | Auto Start Stop condition is established AUTO START STOP (DIAGNOSTICS)>Data Monitor

Common execution condition

• CAN communication for engine is normal.

• Following conditions are established

Items | Value
Ignition Switch(Auto Start Stop) | ON
System Voltage(Auto Start Stop) | 12.1 V or more
Engine Speed(Auto Start Stop) | 0 rpm
Vehicle Speed | 0 km/h (0 MPH)
Idling Stop Control | Other than during control

AUTO START STOP (DIAGNOSTICS) > Customize
OPERATION
1.

On [Start] screen, select [Diagnosis].

2.

On [Select Vehicle] screen, input the target vehicle information and select [Set].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission].

5.

On [Select Function] screen, select [Customize].

- For detailed operation procedures, refer to “Help” of application.

- The setting can be changed when the vehicle is in the following conditions.

  - Ignition switch ON (engine OFF)

  - During vehicle stoppage

Changing the same item several times in a row is not possible. To re-perform the setting after changing the setting, select [Customize] on [Select Function] display.

AUTO START STOP (DIAGNOSTICS) > Customize
LIST

Item | Initial setting value | Customize setting | Note
Turn signal ON stop prohibition | ON | ON | Auto Start Stop is activated even when the turn signal is operating.
OFF | Auto Start Stop is not activated when the turn signal is operating.

AUTO START STOP (DIAGNOSTICS) > Work Support
NOTE

If the starter or TCM is replaced, always clear the start count or transfer the information of start count.

- Starter replacement: Start count clearing AUTO START STOP (DIAGNOSTICS)>Work Support>OPERATION > START COUNT CLEARING

- TCM replacement∗: Start count reading and writing AUTO START STOP (DIAGNOSTICS)>Work Support>OPERATION > START COUNT READING ECU TO SSM AUTO START STOP (DIAGNOSTICS)>Work Support>OPERATION > START COUNT WRITING SSM TO ECU

  ∗ Let the Subaru Select Monitor read “Start Count” before removing the used TCM, and then write these “Start Count” after installing a new TCM.

Preconditions for clearing the start count

- Number of times for starting is other than 0

- Common execution condition is established

Common execution condition

• CAN communication for engine is normal.

• Following conditions are established

Items | Value
Ignition Switch(Auto Start Stop) | ON
System Voltage(Auto Start Stop) | 12.1 V or more
Engine Speed(Auto Start Stop) | 0 rpm
Vehicle Speed | 0 km/h (0 MPH)
Idling Stop Control | Other than during control

AUTO START STOP (DIAGNOSTICS) > Work Support
OPERATION

For detailed operation procedures, refer to “Help” of application.

1. Start count clearing
1.

On [Start] screen, select [Diagnosis].

2.

On [Select Vehicle] screen, enter vehicle information and select [Confirmed].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission].

5.

On [Select Function] screen, select [Work Support].

6.

On [Work Support item] screen, select [Start count clearing].

7.

On [Clear start count?] screen, click the [Yes] button.

8.

On [Done] screen, click the [Next] button to end the start count clearing mode. The display returns to [Work Support item] screen.

9.

Make sure the value of [Start Count] is cleared using Subaru Select Monitor.

2. Start count reading ECU to SSM
1.

On [Start] screen, select [Diagnosis].

2.

On [Select Vehicle] screen, enter vehicle information and select [Confirmed].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission].

5.

On [Select Function] screen, select [Work Support].

6.

On [Work Support item] screen, select [Start count reading ECU to SSM].

7.

On [Start reading of Auto Start Stop unit specifications information?] screen, click the [Yes] button.

8.

On [Save?] screen, click the [OK] button.

9.

On [When saving, enter the VIN No. into the Comment column, so that there is no mistake at the time of writing.] screen, click the [OK] button.

10.

On Save As screen, save the Auto Start Stop file in the suitable location.

Enter the identification information such as VIN No. into the comment column so as not to select a wrong file at the time of start count writing.

11.

On [Turn off the ignition switch.] screen, click the [OK] button to end the start count reading. The display returns to [Work Support item] screen.

3. Start count writing SSM to ECU
1.

On [Start] screen, select [Diagnosis].

2.

On [Select Vehicle] screen, enter vehicle information and select [Confirmed].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission].

5.

On [Select Function] screen, select [Work Support].

6.

On [Work Support item] screen, select [Start count writing SSM to ECU].

7.

On [Writing cannot be executed without engine off Start writing of Auto Start Stop unit specifications information?] screen, click the [Yes] button.

8.

On [Confirm that the input information in the Comment column refers to the object vehicle.] screen, click the [OK] button.

9.

On saved file selection screen, open the suitable Auto Start Stop file.

Make sure that identification information in the comment column refers to the object vehicle so as not to select a wrong file.

10.

On [Register?] screen, click the [OK] button.

11.

On [Registration completed.] screen, click the [OK] button to end the start count writing. The display returns to [Work Support item] screen.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Trouble Code (DTC)
OPERATION

- For detailed operation procedures, refer to “Common (Diagnostics)”. COMMON(diag)>Diagnostic Trouble Code (DTC)

- For details on DTCs, refer to the list. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

AUTO START STOP (DIAGNOSTICS) > Diagnostic Trouble Code (DTC)
LIST

DTC | Item | Note
P0512 | STARTER (SWITCH) REQUEST CIRCUIT | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P0512 STARTER (SWITCH) REQUEST CIRCUIT
P1518 | STARTER SWITCH CIRCUIT LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1518 STARTER SWITCH CIRCUIT LOW
P1567 | AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1567 AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT LOW
P1568 | AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT HIGH | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1568 AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT HIGH
P1580 | STARTER RELAY DIAGNOSIS CIRCUIT | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1580 STARTER RELAY DIAGNOSIS CIRCUIT
P1615 | STARTER OPERATION NUMBER OF TIMES EXCESS | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1615 STARTER OPERATION NUMBER OF TIMES EXCESS
P161D | ELECTRIC FLUID PUMP (CVT) RELAY CIRCUIT LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P161D ELECTRIC FLUID PUMP (CVT) RELAY CIRCUIT LOW
P1625 | AUTO START REQUEST CIRCUIT LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1625 AUTO START REQUEST CIRCUIT LOW
P1626 | AUTO START REQUEST CIRCUIT HIGH | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1626 AUTO START REQUEST CIRCUIT HIGH
P1739 | ELECTRIC FLUID PUMP (CVT) DRIVE CIRCUIT | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1739 ELECTRIC FLUID PUMP (CVT) DRIVE CIRCUIT
P173A | ELECTRIC FLUID PUMP (CVT) STATUS SIGNAL | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P173A ELECTRIC FLUID PUMP (CVT) STATUS SIGNAL
P173B | ELECTRIC FLUID PUMP (CVT) PERFORMANCE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P173B ELECTRIC FLUID PUMP (CVT) PERFORMANCE
P173C | ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P173C ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT LOW
P173D | ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT HIGH | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P173D ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT HIGH
P173E | ELECTRIC FLUID PUMP (CVT) INPUT VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P173E ELECTRIC FLUID PUMP (CVT) INPUT VOLTAGE
P1A15 | DC/DC CONVERTER 1 BOOST COMMAND SIGNAL LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A15 DC/DC CONVERTER 1 BOOST COMMAND SIGNAL LOW
P1A16 | DC/DC CONVERTER 1 BOOST COMMAND SIGNAL HIGH | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A16 DC/DC CONVERTER 1 BOOST COMMAND SIGNAL HIGH
P1A17 | DC/DC CONVERTER 2 BOOST COMMAND SIGNAL LOW | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A17 DC/DC CONVERTER 2 BOOST COMMAND SIGNAL LOW
P1A18 | DC/DC CONVERTER 2 BOOST COMMAND SIGNAL HIGH | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A18 DC/DC CONVERTER 2 BOOST COMMAND SIGNAL HIGH
P1A20 | DC/DC CONVERTER 1 BOOST PERFORMANCE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A20 DC/DC CONVERTER 1 BOOST PERFORMANCE
P1A21 | DC/DC CONVERTER 1 INPUT 1 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A21 DC/DC CONVERTER 1 INPUT 1 VOLTAGE
P1A22 | DC/DC CONVERTER 1 INPUT 2 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A22 DC/DC CONVERTER 1 INPUT 2 VOLTAGE
P1A23 | DC/DC CONVERTER 1 OUTPUT 1 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A23 DC/DC CONVERTER 1 OUTPUT 1 VOLTAGE
P1A24 | DC/DC CONVERTER 1 OUTPUT 2 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A24 DC/DC CONVERTER 1 OUTPUT 2 VOLTAGE
P1A25 | DC/DC CONVERTER 1 CIRCUIT 1 TEMPERATURE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A25 DC/DC CONVERTER 1 CIRCUIT 1 TEMPERATURE
P1A26 | DC/DC CONVERTER 1 CIRCUIT 2 TEMPERATURE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A26 DC/DC CONVERTER 1 CIRCUIT 2 TEMPERATURE
P1A27 | DC/DC CONVERTER 1 INTERNAL CIRCUIT | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A27 DC/DC CONVERTER 1 INTERNAL CIRCUIT
P1A28 | DC/DC CONVERTER 2 BOOST PERFORMANCE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A28 DC/DC CONVERTER 2 BOOST PERFORMANCE
P1A29 | DC/DC CONVERTER 2 INPUT 1 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A29 DC/DC CONVERTER 2 INPUT 1 VOLTAGE
P1A2A | DC/DC CONVERTER 2 INPUT 2 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2A DC/DC CONVERTER 2 INPUT 2 VOLTAGE
P1A2B | DC/DC CONVERTER 2 OUTPUT 1 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2B DC/DC CONVERTER 2 OUTPUT 1 VOLTAGE
P1A2C | DC/DC CONVERTER 2 OUTPUT 2 VOLTAGE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2C DC/DC CONVERTER 2 OUTPUT 2 VOLTAGE
P1A2D | DC/DC CONVERTER 2 CIRCUIT 1 TEMPERATURE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2D DC/DC CONVERTER 2 CIRCUIT 1 TEMPERATURE
P1A2E | DC/DC CONVERTER 2 CIRCUIT 2 TEMPERATURE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2E DC/DC CONVERTER 2 CIRCUIT 2 TEMPERATURE
P1A2F | DC/DC CONVERTER 2 INTERNAL CIRCUIT | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2F DC/DC CONVERTER 2 INTERNAL CIRCUIT
P1C00 | BATTERY MONITOR MODULE "A" PERFORMANCE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1C00 BATTERY MONITOR MODULE "A" PERFORMANCE
P257E | Engine Hood Switch Circuit Low | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P257E ENGINE HOOD SWITCH CIRCUIT LOW
P257F | Engine Hood Switch Circuit High | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P257F ENGINE HOOD SWITCH CIRCUIT HIGH
U0073 | CONTROL MODULE COMMUNICATION BUS OFF | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF
U0100 | LOST COMMUNICATION WITH ECM/PCM "A" | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"
U0122 | LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE
U0128 | LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0128 LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE
U0131 | LOST COMMUNICATION WITH POWER STEERING CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0131 LOST COMMUNICATION WITH POWER STEERING CONTROL MODULE
U0140 | LOST COMMUNICATION WITH BODY CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0140 LOST COMMUNICATION WITH BODY CONTROL MODULE
U0155 | LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE
U0164 | LOST COMMUNICATION WITH HVAC CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0164 LOST COMMUNICATION WITH HVAC CONTROL MODULE
U0401 | INVALID DATA RECEIVED FROM ECM/PCM "A" | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0401 INVALID DATA RECEIVED FROM ECM/PCM "A"
U0416 | INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE
U0417 | INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0417 INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE
U0420 | INVALID DATA RECEIVED FROM POWER STEERING CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0420 INVALID DATA RECEIVED FROM POWER STEERING CONTROL MODULE
U0422 | INVALID DATA RECEIVED FROM BODY CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0422 INVALID DATA RECEIVED FROM BODY CONTROL MODULE
U0423 | INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUSTER CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0423 INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUSTER CONTROL MODULE
U0424 | INVALID DATA RECEIVED FROM HVAC CONTROL MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0424 INVALID DATA RECEIVED FROM HVAC CONTROL MODULE
U1604 | LOST COMMUNICATION WITH DC/DC CONVERTER MODULE 1 | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1604 LOST COMMUNICATION WITH DC/DC CONVERTER MODULE 1
U1712 | LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR MODULE | AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1712 LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P0512 STARTER (SWITCH) REQUEST CIRCUIT
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
2. CHECK INPUT VOLTAGE OF TCM.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON. (Engine OFF)

2.

Read the data of [Starter Switch] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [ON] displayed in [Starter Switch]?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK INPUT VOLTAGE OF TCM.
1.

Turn the ignition switch to OFF.

2.

Disconnect the TCM connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between TCM and chassis ground.

Connector & terminal

(T10) No. 45 (+) — Chassis ground (−):

Is the voltage 10 V or more?

- Check the following item and repair if necessary.

  - Model with push button start

    Repair the short circuit to power supply in harness between keyless access CM and TCM connector.

  - Model without push button start

    Short circuit to power supply in harness between ignition switch and TCM connector

    Sticking inside the ignition switch

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the short circuit in the starter switch circuit.

- Judge as NG when the starter switch ON is detected after engine start.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1518 STARTER SWITCH CIRCUIT LOW
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
2. CHECK INPUT VOLTAGE OF TCM.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.

Read the data of [Starter Switch] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [OFF] displayed in [Starter Switch]?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK INPUT VOLTAGE OF TCM.
1.

Turn the ignition switch to OFF.

2.

Disconnect the TCM connector.

3.

Start the engine.

4.

Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(T10) No. 45 (+) — Chassis ground (−):

Is the voltage less than 1 V?

- Check the following item and repair if necessary.

  - Model with push button start

    Repair the open circuit of harness between keyless access CM and TCM connector.

  - Model without push button start

    Open harness between ignition switch and TCM connector

    Poor contact inside the ignition switch

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect open or short circuit of the starter switch circuits.

- Judge as NG when there is no ON experience of the starter switch when the engine is started except for restarting by Auto Start Stop.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1567 AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT LOW
1. —

DTC detecting condition:

Detected when five consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Audio system and navigation system do not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DTC.
yes

Perform the instructed procedures.

no

2

2. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
3. CHECK INPUT SIGNAL OF ECM.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.
1.

Turn the ignition switch to ON.

2.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is P1A21, P1A23 or P1A27 displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK DATA MONITOR.

Read the data of [Audio Supply Voltage] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is the value of [Audio Supply Voltage] less than 5 V?

3

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

3. CHECK INPUT SIGNAL OF ECM.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 63 (+) — Chassis ground (−):

Is the voltage less than 5 V?

Repair the open circuit of harness and poor contact of coupling connector between ECM and DC/DC converter 1.

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

General description
OUTLINE OF DIAGNOSIS

- Detect the open or short circuit in the DC/DC voltage monitor circuit.

- Judge as NG when the voltage of the DC/DC voltage monitor circuit is out of standard.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 1 s or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[System Voltage(Auto Start Stop)] | 12 V or more
[Audio Supply Voltage] | Less than 2.5 V

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1568 AUDIO SUPPLY VOLTAGE MONITORING CIRCUIT HIGH
1. —

DTC detecting condition:

Detected when ten consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DTC.
yes

Perform the instructed procedures.

no

2

2. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
3. CHECK INPUT SIGNAL OF ECM.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.
1.

Turn the ignition switch to ON.

2.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is P1A23 displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK DATA MONITOR.
1.

Start the engine and let it idle.

2.

Read the data of [Audio Supply Voltage] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is the value of [Audio Supply Voltage] 15 V or more?

3

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

3. CHECK INPUT SIGNAL OF ECM.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 63 (+) — Chassis ground (−):

Is the voltage 15 V or more?

Replace the DC/DC converter 1. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

General description
OUTLINE OF DIAGNOSIS

- Detect the short circuit in the DC/DC voltage monitor circuit.

- Judge as NG when the voltage of the DC/DC voltage monitor circuit is out of standard.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 1 s or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[System Voltage(Auto Start Stop)] | Less than 12.8 V
[Audio Supply Voltage] | 15 V or more

Time needed for diagnosis: 1 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1580 STARTER RELAY DIAGNOSIS CIRCUIT
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

6

yes
2. CHECK STARTER RELAY.
yes

Perform the instructed procedures.

no

3

3. CHECK HARNESS BETWEEN STARTER RELAY AND ECM CONNECTOR.
no

Perform the instructed procedures.

yes
4. CHECK OUTPUT SIGNAL OF ECM.
no

Perform the instructed procedures.

yes
5. CHECK HARNESS BETWEEN STARTER RELAY AND STARTER CUT RELAY AND ECM CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

6. CHECK DATA MONITOR.
no

11

yes
7. CHECK STARTER CUT RELAY.
yes

Perform the instructed procedures.

no

8

8. CHECK HARNESS BETWEEN STARTER RELAY AND ECM CONNECTOR.
no

Perform the instructed procedures.

yes
9. CHECK OUTPUT SIGNAL OF ECM.
no

Perform the instructed procedures.

yes
10. CHECK HARNESS BETWEEN STARTER RELAY AND STARTER CUT RELAY AND ECM CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

11. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

12

12. CHECK HARNESS BETWEEN M/B AND ECM CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [Starter Relay Diagnosis A/D Value] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Is the value of [Starter Relay Diagnosis A/D Value] less than 2 V?

2

6

2. CHECK STARTER RELAY.
1.

Turn the ignition switch to OFF.

2.

Remove the starter relay.

3.

Measure the resistance between starter relay terminals.

Terminals

No. 1 — No. 3:

Is the resistance less than 1 Ω?

Replace the starter relay.

3

3. CHECK HARNESS BETWEEN STARTER RELAY AND ECM CONNECTOR.
1.

Disconnect the ECM connector.

2.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B134) No. 2 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Repair the short circuit to ground in harness between starter relay and ECM connector.

4. CHECK OUTPUT SIGNAL OF ECM.
1.

Install the starter relay.

2.

Turn the ignition switch to ON.

3.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 2 (+) — Chassis ground (−):

Is the voltage 12 V or more?

5

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

5. CHECK HARNESS BETWEEN STARTER RELAY AND STARTER CUT RELAY AND ECM CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B134) No. 45 — Chassis ground:

Is the resistance 1 MΩ or more?

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

Repair the short circuit to ground in harness between starter relay or starter cut relay and ECM connector.

6. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [Starter Relay Diagnosis A/D Value] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Is [Starter Relay Diagnosis A/D Value] 10 V or more?

7

11

7. CHECK STARTER CUT RELAY.
1.

Turn the ignition switch to OFF.

2.

Remove the starter cut relay.

3.

Measure the resistance between starter cut relay terminals.

Terminals

No. 1 — No. 3:

Is the resistance less than 1 Ω?

Replace the starter cut relay.

8

8. CHECK HARNESS BETWEEN STARTER RELAY AND ECM CONNECTOR.
1.

Disconnect the ECM connector.

2.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B134) No. 24 — Chassis ground:

Is the resistance 1 MΩ or more?

9

Repair the short circuit to ground in harness between starter cut relay and ECM connector.

9. CHECK OUTPUT SIGNAL OF ECM.
1.

Install the starter cut relay.

2.

Turn the ignition switch to ON.

3.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 24 (+) — Chassis ground (−):

Is the voltage 12 V or more?

10

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

10. CHECK HARNESS BETWEEN STARTER RELAY AND STARTER CUT RELAY AND ECM CONNECTOR.
1.

Turn the ignition switch to ON.

2.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 45 (+) — Chassis ground (−):

Is the voltage 12 V or more?

Repair the short circuit to power supply in harness between starter relay or starter cut relay and ECM connector.

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

11. CHECK DATA MONITOR.
1.

Connect the ECM connector.

2.

Read the data of [Starter Relay Diagnosis A/D Value] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Read the data from Ignition switch ON to Engine being started.

Does the [Starter Relay Diagnosis A/D Value] exceed 10 V?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

12

12. CHECK HARNESS BETWEEN M/B AND ECM CONNECTOR.
1.

Disconnect the connector of ECM connector.

2.

Measure the resistance of harness between M/B and ECM connector.

Connector & terminal

(M/B) Starter relay No. 4 — (B134) No. 2:

(M/B) Starter cut relay No. 4 — (B134) No. 24:

Is the resistance less than 1 Ω?

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

Repair the open circuit of harness and poor contact of coupling connector between M/B and ECM connector.

General description
OUTLINE OF DIAGNOSIS

- Detect a stuck to ON in the starter relay/starter cut relay, and starter diagnosis input circuit failure.

- Judge as NG if the input voltage of starter diagnosis is out of specification.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1615 STARTER OPERATION NUMBER OF TIMES EXCESS
1. —

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Auto Start Stop does not operate.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [Start Count] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is the value of [Start Count] 280000 times or more?

Replace the starter and fuel pump relay at the same time. STARTING/CHARGING SYSTEMS(H4DO)>Starter AUTO START STOP (DIAGNOSTICS)>Electrical Component Location

Replace the TCM. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the excessive counts of starter operation.

- Judge as NG if the number of starter operation counts exceeds the predetermined value.

EXECUTION CONDITION

Secondary parameters | Execution condition
Ignition switch | ON

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Start Count] | 280000 times or more

Time Needed for Diagnosis: Immediately

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P161D ELECTRIC FLUID PUMP (CVT) RELAY CIRCUIT LOW
1. —

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP CONNECTOR AND RELAY HOLDER.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN TCM AND RELAY HOLDER.
no

Perform the instructed procedures.

yes
3. CHECK ELECTRIC OIL PUMP RELAY.
no

Perform the instructed procedures.

yes
4. CHECK TCM OUTPUT VOLTAGE.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP CONNECTOR AND RELAY HOLDER.
1.

Turn the ignition switch to OFF.

2.

Remove the electric oil pump relay.

3.

Disconnect the connector from electric oil pump.

4.

Turn the ignition switch to ON.

5.

Measure the voltage between electric oil pump connector and chassis ground.

Connector & terminal

(T27) No. 4 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair the short circuit to power supply in the harness between electric oil pump connector and relay holder.

2

2. CHECK HARNESS BETWEEN TCM AND RELAY HOLDER.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector from TCM.

3.

Measure the resistance between TCM connector and chassis ground.

Connector & terminal

(T10) No. 22 — Chassis ground:

Is the resistance 1 MΩ or more?

3

Repair the short circuit to ground in harness between TCM and relay holder.

3. CHECK ELECTRIC OIL PUMP RELAY.

Measure the resistance between electric oil pump relay terminals.

Terminals

No. 39 — No. 40:

Is the resistance 1 MΩ or more?

4

Replace the electric oil pump relay. AUTO START STOP (DIAGNOSTICS)>Electrical Component Location

4. CHECK TCM OUTPUT VOLTAGE.
1.

Connect all connectors.

2.

Install the electric oil pump relay.

3.

Turn the ignition switch to ON.

4.

Perform the active test using Subaru Select Monitor to drive the electric oil pump relay. AUTO START STOP (DIAGNOSTICS)>Active Test

5.

Measure the voltage between TCM and chassis ground.

Connector & terminal

(T10) No. 22 (+) — Chassis ground (−):

Does the voltage change according to relay ON/OFF? (0 V ←→ 12 V)

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

  In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the electric oil pump relay ON stuck and short circuit in the electric oil pump relay circuits.

- Judge as NG when signals are received from the electric oil pump driver while the electric oil pump relay is OFF.

EXECUTION CONDITION

Secondary parameters | Execution condition
After IG ON | 1 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more and Less than 15 V
[Electric Fluid Pump Relay(Auto Start Stop)] | OFF

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Electric oil pump diagnosis duty cycle] | Other than 0%

Time needed for diagnosis: 3 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1625 AUTO START REQUEST CIRCUIT LOW
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK HARNESS BETWEEN ECM CONNECTOR AND TCM CONNECTOR.
no

Perform the instructed procedures.

yes
2. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
3. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK HARNESS BETWEEN ECM CONNECTOR AND TCM CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Disconnect the TCM connector.

4.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(E158) No. 36 — Chassis ground:

Is the resistance 1 MΩ or more?

2

Repair the short circuit to ground in harness between ECM connector and TCM connector.

2. CHECK DATA MONITOR.
1.

Connect the ECM connector.

2.

Turn the ignition switch to ON.

3.

Read the data of [Restart Commanded Signal] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Is “OFF” displayed in [Restart Commanded Signal]?

3

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

3. CHECK DATA MONITOR.
1.

Connect the TCM connector.

2.

Turn the ignition switch to ON.

3.

Read the data of [Restart Commanded Signal] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Is “OFF” displayed in [Restart Commanded Signal]?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the short circuit in the start command circuit.

- Judge as NG when the command and monitoring status do not correspond.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1626 AUTO START REQUEST CIRCUIT HIGH
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the TCM/ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN ECM CONNECTOR AND TCM CONNECTOR.
no

Perform the instructed procedures.

yes
3. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [Restart Commanded Signal] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

Start the engine and drive at 5 km/h (3 MPH) or more.

Does the display of [Restart Commanded Signal] change to ON while driving?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2

2. CHECK HARNESS BETWEEN ECM CONNECTOR AND TCM CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Disconnect the TCM connector.

4.

Measure the resistance between ECM connector and TCM connector.

Connector & terminal

(E158) No. 36 — (T10) No. 23:

Is the resistance less than 1 Ω?

3

Repair the open circuit of harness and poor contact of coupling connector between ECM connector and TCM connector.

3. CHECK DATA MONITOR.
1.

Connect the ECM connector.

2.

Turn the ignition switch to ON.

3.

Read the data of [Restart Commanded Signal] in [Engine] using Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Data Monitor

4.

Short the terminal No. 23 of TCM connector to ground.

Does the display of [Restart Commanded Signal] change to ON?

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the open circuit in the start command circuit.

- Judge as NG when the command and monitoring status do not correspond.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1739 ELECTRIC FLUID PUMP (CVT) DRIVE CIRCUIT
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
no

Perform the instructed procedures.

yes
3. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
no

Perform the instructed procedures.

yes
4. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the TCM connector.

3.

Disconnect the connector of electric oil pump.

4.

Turn the ignition switch to ON.

5.

Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(T10) No. 21 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair the short circuit to power supply in the harness between TCM and electric oil pump connector.

2

2. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Measure the resistance between TCM connector and chassis ground.

Connector & terminal

(T10) No. 21 — Chassis ground:

Is the resistance 1 MΩ or more?

3

Repair the short circuit to ground in the harness between TCM and electric oil pump connector.

3. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.

Measure the resistance in harness between TCM connector and electric oil pump connector.

Connector & terminal

(T10) No. 21 — (T27) No. 3:

Is the resistance less than 1 Ω?

4

Repair the open circuit in harness between TCM connector and electric oil pump connector.

4. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.
1.

Connect all connectors.

2.

Turn the ignition switch to ON.

3.

Read the waveform of electric oil pump operation command signal using an oscilloscope.

Connector & terminal

(T10) No. 21 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation command signal 5 — 95%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the electric oil pump driver, open or short circuit in the electric oil pump relay circuits.

- Judge as NG when the electric oil pump driver detects malfunction of the electric oil pump drive system circuit.

EXECUTION CONDITION

Secondary parameters | Execution condition
After IG ON | 1 s or more
[Electric Fluid Pump Relay(Auto Start Stop)] | ON
[System Voltage(Auto Start Stop)] | 10.5 V or more and Less than 15 V

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Electric oil pump diagnosis duty cycle] | 56% — 63%

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P173A ELECTRIC FLUID PUMP (CVT) STATUS SIGNAL
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
no

Perform the instructed procedures.

yes
2. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

4

no

3

3. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

4. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

Perform the instructed procedures.

no

5

5. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Operate Auto Start Stop after driving the vehicle, then restart the engine by pressing the Auto Start Stop cancel switch.

Even if Auto Start Stop does not operate, go to step 4).

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) three times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Turn the ignition switch to ON.

2.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 30%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

4

3

3. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.

Read the waveform of electric oil pump operation command signal using an oscilloscope.

Connector & terminal

(T10) No. 21 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation command signal 10%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

4. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Start the engine.

2.

Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. AUTO START STOP (DIAGNOSTICS)>Active Test

3.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 50%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

5

5. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL.
1.

Start the engine.

2.

Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. AUTO START STOP (DIAGNOSTICS)>Active Test

3.

Read the waveform of electric oil pump operation command signal using an oscilloscope.

Connector & terminal

(T10) No. 21 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation command signal 65%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the electric oil pump driver.

- Judge as NG when malfunction of the electric oil pump driver is detected.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P173B ELECTRIC FLUID PUMP (CVT) PERFORMANCE
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
no

Perform the instructed procedures.

yes
2. CHECK STATUS AT DTC MEMORY.
yes

4

no

3

3. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

4. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Operate Auto Start Stop after driving the vehicle, then restart the engine by pressing the Auto Start Stop cancel switch.

Even if Auto Start Stop does not operate, go to step 4).

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) three times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK STATUS AT DTC MEMORY.

Is the DTC memory set after Auto Start Stop is activated?

4

3

3. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Start the engine.

2.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 30%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

4. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. AUTO START STOP (DIAGNOSTICS)>Active Test

4.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 50%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

General description
OUTLINE OF DIAGNOSIS

- Detect the malfunction of the electric oil pump operation, and abnormal voltage and current of the electric oil pump driver.

- Judge as NG when the electric oil pump driver detects an operational malfunction, abnormal voltage or current in the electric oil pump.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P173C ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT LOW
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
no

Perform the instructed procedures.

yes
2. CHECK ELECTRIC OIL PUMP DIAGNOSIS SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the TCM connector.

3.

Disconnect the connector of electric oil pump.

4.

Measure the resistance between TCM connector and chassis ground.

Connector & terminal

(T10) No. 7 — Chassis ground:

Is the resistance 1 MΩ or more?

2

Repair the short circuit to ground in the harness between TCM and electric oil pump connector.

2. CHECK ELECTRIC OIL PUMP DIAGNOSIS SIGNAL.
1.

Connect the TCM connector.

2.

Turn the ignition switch to ON.

3.

Read the data of [Electric oil pump diagnosis duty cycle] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is the value of [Electric oil pump diagnosis duty cycle] 0%?

Replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the electric oil pump driver and short circuit in the electric oil pump status circuits.

- Judge as NG when the electric oil pump status signal is always LOW.

EXECUTION CONDITION

Secondary parameters | Execution condition
After IG ON | 1 s or more
[Electric Fluid Pump Relay(Auto Start Stop)] | ON
[System Voltage(Auto Start Stop)] | 10.5 V or more and Less than 15 V

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Electric oil pump diagnosis duty cycle] | 100%

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P173D ELECTRIC FLUID PUMP (CVT) STATUS CIRCUIT HIGH
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK POWER SUPPLY OF ELECTRIC OIL PUMP RELAY.
no

Perform the instructed procedures.

yes
2. CHECK HARNESS BETWEEN TCM CONNECTOR AND RELAY HOLDER.
no

Perform the instructed procedures.

yes
3. CHECK ELECTRIC OIL PUMP RELAY UNIT.
no

Perform the instructed procedures.

yes
4. CHECK TCM OUTPUT VOLTAGE.
yes

Perform the instructed procedures.

no

5

5. CHECK HARNESS BETWEEN TCM CONNECTOR AND ELECTRIC OIL PUMP CONNECTOR.
no

Perform the instructed procedures.

yes
6. CHECK HARNESS BETWEEN RELAY HOLDER AND ELECTRIC OIL PUMP CONNECTOR.
no

Perform the instructed procedures.

yes
7. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP AND CHASSIS GROUND.
no

Perform the instructed procedures.

yes
8. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK POWER SUPPLY OF ELECTRIC OIL PUMP RELAY.
1.

Turn the ignition switch to OFF.

2.

Remove the electric oil pump relay.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between relay holder and chassis ground.

Connector & terminal

(B225) No. 38 (+) — Chassis ground (−):

(B225) No. 39 (+) — Chassis ground (−):

Is the voltage 10 V or more?

2

Repair the open or ground short in the harness of power supply circuit.

2. CHECK HARNESS BETWEEN TCM CONNECTOR AND RELAY HOLDER.
1.

Turn the ignition switch to OFF.

2.

Disconnect the TCM connector.

3.

Measure the resistance in harness between TCM connector and relay holder.

Connector & terminal

(T10) No. 22 — (B225) No. 37:

Is the resistance less than 1 Ω?

3

Repair the open circuit of harness between TCM connector and relay holder.

3. CHECK ELECTRIC OIL PUMP RELAY UNIT.

Check the electric oil pump relay unit. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Relay and Fuse>INSPECTION > CHECK RELAY

Is the check result OK?

4

Replace the electric oil pump relay. AUTO START STOP (DIAGNOSTICS)>Electrical Component Location

4. CHECK TCM OUTPUT VOLTAGE.
1.

Connect the TCM connector.

2.

Install the electric oil pump relay.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(T10) No. 22 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

5

5. CHECK HARNESS BETWEEN TCM CONNECTOR AND ELECTRIC OIL PUMP CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector of electric oil pump.

3.

Measure the resistance in harness between TCM connector and electric oil pump connector.

Connector & terminal

(T10) No. 7 — (T27) No. 2:

Is the resistance less than 1 Ω?

6

Repair the open circuit in harness between TCM connector and electric oil pump connector.

6. CHECK HARNESS BETWEEN RELAY HOLDER AND ELECTRIC OIL PUMP CONNECTOR.
1.

Remove the electric oil pump relay.

2.

Measure the resistance in harness between relay holder and electric oil pump connector.

Connector & terminal

(B225) No. 40 — (T27) No. 4:

Is the resistance less than 1 Ω?

7

Repair the open circuit of harness and poor contact of coupling connector between relay holder and electric oil pump connector.

7. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP AND CHASSIS GROUND.

Measure the resistance of harness between electric oil pump connector and chassis ground.

Connector & terminal

(T27) No. 1 — Chassis ground:

Is the resistance less than 5 Ω?

8

Repair the open circuit in harness between electric oil pump connector and chassis ground.

8. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Connect the connector of the electric oil pump.

2.

Install the electric oil pump relay.

3.

Turn the ignition switch to ON.

4.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 0%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Check for the poor contact in electric oil pump connector. If no fault is found, replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect the malfunction of the electric oil pump driver, and open or short circuit in the electric oil pump status circuits.

- Judge as NG when the electric oil pump status signal is always HIGH.

EXECUTION CONDITION

Secondary parameters | Execution condition
After IG ON | 1 s or more
[Electric Fluid Pump Relay(Auto Start Stop)] | ON
[System Voltage(Auto Start Stop)] | 10.5 V or more and Less than 15 V

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Electric oil pump diagnosis duty cycle] | 0%

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P173E ELECTRIC FLUID PUMP (CVT) INPUT VOLTAGE
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

CVT control system WIRING SYSTEM>CVT Control System

- Use the check board when measuring the TCM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK POWER SUPPLY OF ELECTRIC OIL PUMP.
no

Perform the instructed procedures.

yes
2. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP CONNECTOR AND CHASSIS GROUND.
no

Perform the instructed procedures.

yes
3. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK POWER SUPPLY OF ELECTRIC OIL PUMP.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector from electric oil pump.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between electric oil pump connector and chassis ground.

Connector & terminal

(T27) No. 4 (+) — Chassis ground (−):

Is the voltage 10 V or more?

2

Repair the open or ground short in the harness of power supply circuit.

2. CHECK HARNESS BETWEEN ELECTRIC OIL PUMP CONNECTOR AND CHASSIS GROUND.
1.

Turn the ignition switch to OFF.

2.

Measure the resistance of harness between electric oil pump connector and chassis ground.

Connector & terminal

(T27) No. 1 — Chassis ground:

Is the resistance less than 5 Ω?

3

Repair the open circuit in harness between electric oil pump connector and chassis ground.

3. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL.
1.

Connect the connector of the electric oil pump.

2.

Turn the ignition switch to ON.

3.

Read the waveform of electric oil pump operation status signal using an oscilloscope.

Connector & terminal

(T10) No. 7 (+) — Chassis ground (−):

Is the duty ratio of electric oil pump operation status signal 77 — 83%? AUTO START STOP (DIAGNOSTICS)>Control Module I/O Signal>WAVEFORM

Replace the electric oil pump. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Electric Fluid Pump

Check for poor contact of TCM connector. Replace the TCM if no fault is found. CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM)

General description
OUTLINE OF DIAGNOSIS

- Detect low voltage of the electric oil pump driver.

- Judge as NG when a low voltage is detected for the electric oil pump driver.

EXECUTION CONDITION

Secondary parameters | Execution condition
After IG ON | 1 s or more
[Electric Fluid Pump Relay(Auto Start Stop)] | ON
[System Voltage(Auto Start Stop)] | 10.5 V or more and Less than 15 V

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Electric oil pump diagnosis duty cycle] | 76% — 83%

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A15 DC/DC CONVERTER 1 BOOST COMMAND SIGNAL LOW
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio or navigation system is reset.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK SYSTEM OPERATION STATUS IN TCM.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
4. CHECK DC/DC BOOST OUTPUT SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK SYSTEM OPERATION STATUS IN TCM.
1.

Using the Subaru Select Monitor, perform the active test [Sub power supply control (ON/OFF Dr.)]. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

Read the data of [DC/DC Converter 1 Boost Signal Reception] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Does the display of [DC/DC Converter 1 Boost Signal Reception] change from [OFF] to [ON] according to the ON/OFF operation?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Disconnect the DC/DC converter 1 connector.

4.

Measure the resistance in harness between ECM connector and DC/DC converter 1 connector.

Connector & terminal

(B134) No. 7 — (B562) No. 11:

Is the resistance less than 1 Ω?

3

Repair the open circuit in harness between ECM and DC/DC converter 1.

3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Repair the short circuit to ground in harness between ECM and DC/DC converter 1.

4. CHECK DC/DC BOOST OUTPUT SIGNAL.
1.

Connect the ECM connector.

2.

Turn the ignition switch to ON.

3.

Using the Subaru Select Monitor, perform the active test [Sub power supply control (ON/OFF Dr.)]. AUTO START STOP (DIAGNOSTICS)>Active Test

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 (+) — Chassis ground (−):

Is the voltage still less than 5 V after ON/OFF operation?

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

General description
OUTLINE OF DIAGNOSIS

- Detect open or short circuit of sub power supply booster signal circuit.

- Judge as NG when the DC/DC converter 1 does not receive boost command when the boost command is issued.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[DC/DC Converter 1 Boost Signal Reception] | Not yet received

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A16 DC/DC CONVERTER 1 BOOST COMMAND SIGNAL HIGH
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
2. CHECK DC/DC CONVERTER 1 BOOST COMMAND SIGNAL.
no

Perform the instructed procedures.

yes
3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [DC/DC Converter 1 Boost Signal Reception] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is “ON” displayed in [DC/DC Converter 1 Boost Signal Reception]?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK DC/DC CONVERTER 1 BOOST COMMAND SIGNAL.
1.

Turn the ignition switch to OFF.

2.

Disconnect the DC/DC converter 1 connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between DC/DC converter 1 connector and chassis ground.

Connector & terminal

(B562) No. 11 (+) — Chassis ground (−):

Is the voltage 5 V or more?

3

Repair the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if defective. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 (+) — Chassis ground (−):

Is the voltage 5 V or more?

Repair the short circuit to power supply in harness between ECM and DC/DC converter 1.

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

General description
OUTLINE OF DIAGNOSIS

- Detect short circuit of sub power supply boost signal system circuit.

- Judge as NG when the DC/DC converter 1 receives boost command while boost command is not issued.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[DC/DC Converter 1 Boost Signal Reception] | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A17 DC/DC CONVERTER 2 BOOST COMMAND SIGNAL LOW
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio or navigation system is reset.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK SYSTEM OPERATION STATUS IN TCM.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
4. CHECK DC/DC BOOST OUTPUT SIGNAL.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK SYSTEM OPERATION STATUS IN TCM.
1.

Using the Subaru Select Monitor, perform the active test [Sub power supply control (ON/OFF Dr.)]. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

Read the data of [DC/DC Converter 2 Boost Signal Reception] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Does the display of [DC/DC Converter 2 Boost Signal Reception] change from [OFF] to [ON] according to the ON/OFF operation?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Disconnect the DC/DC converter 2 connector.

4.

Measure the resistance in harness between ECM connector and DC/DC converter 2 connector.

Connector & terminal

(B134) No. 7 — (B630) No. 3:

Is the resistance less than 1 Ω?

3

Repair the open circuit in harness between ECM and DC/DC converter 2.

3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Repair the short circuit to ground in harness between ECM and DC/DC converter 2.

4. CHECK DC/DC BOOST OUTPUT SIGNAL.
1.

Connect the ECM connector.

2.

Turn the ignition switch to ON.

3.

Using the Subaru Select Monitor, perform the active test [Sub power supply control (ON/OFF Dr.)]. AUTO START STOP (DIAGNOSTICS)>Active Test

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 (+) — Chassis ground (−):

Is the voltage still less than 5 V after ON/OFF operation?

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

General description
OUTLINE OF DIAGNOSIS

- Detect open or short circuit of sub power supply booster signal circuit.

- Judge as NG when the DC/DC converter 2 does not receive boost command when the boost command is issued.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[DC/DC Converter 2 Boost Signal Reception] | Not yet received

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A18 DC/DC CONVERTER 2 BOOST COMMAND SIGNAL HIGH
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
2. CHECK DC/DC CONVERTER 2 BOOST COMMAND SIGNAL.
no

Perform the instructed procedures.

yes
3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [DC/DC Converter 2 Boost Signal Reception] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is “ON” displayed in [DC/DC Converter 2 Boost Signal Reception]?

2

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

2. CHECK DC/DC CONVERTER 2 BOOST COMMAND SIGNAL.
1.

Turn the ignition switch to OFF.

2.

Disconnect the DC/DC converter 2 connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between DC/DC converter 2 connector and chassis ground.

Connector & terminal

(B630) No. 3 (+) — Chassis ground (−):

Is the voltage 5 V or more?

3

Repair the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if defective. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

3. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 2.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Turn the ignition switch to ON.

4.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B134) No. 7 (+) — Chassis ground (−):

Is the voltage 5 V or more?

Repair the short circuit to power supply in harness between ECM and DC/DC converter 2.

Check for poor contact of ECM connector. Replace the ECM if no fault is found. FUEL INJECTION (FUEL SYSTEMS)(H4DO)>Engine Control Module (ECM)

General description
OUTLINE OF DIAGNOSIS

- Detect short circuit of sub power supply boost signal system circuit.

- Judge as NG when the DC/DC converter 2 receives boost command while boost command is not issued.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[DC/DC Converter 2 Boost Signal Reception] | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A20 DC/DC CONVERTER 1 BOOST PERFORMANCE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio or navigation system is reset.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK FOR ANY OTHER DTC ON DISPLAY.
yes

Perform the instructed procedures.

no

2

2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK FOR ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Perform the diagnosis according to DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the DC/DC converter 1 at boosting.

- Judge as NG when the DC/DC converter 1 detects malfunction at boosting.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Malfunction at boosting from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A21 DC/DC CONVERTER 1 INPUT 1 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Power for audio and navigation system will not turn on.

- MFD does not operate.

- Doors cannot be opened/closed with keyless access system.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.

Turn the ignition switch to ON, and turn on the audio or navigation system.

Is it powered on?

3

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B563) No. 3 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal input of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal input of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 input from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A22 DC/DC CONVERTER 1 INPUT 2 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Power for audio and navigation system will not turn on.

- Illumination does not illuminate.

- Combination meter does not operate.

- A/C does not operate.

- VDC does not operate.

- EyeSight does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.
1.

Start the engine.

2.

Check the combination meter condition.

Does the combination meter operate normally?

3

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B563) No. 5 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal input of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal input of ch2.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 input from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A23 DC/DC CONVERTER 1 OUTPUT 1 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Power for audio and navigation system will not turn on.

- MFD does not operate.

- Doors cannot be opened/closed with keyless access system.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.

Turn the ignition switch to ON, and turn on the audio or navigation system.

Is it powered on?

3

2

2. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B563) No. 1 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal output of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal output of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 output from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A24 DC/DC CONVERTER 1 OUTPUT 2 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Power for audio and navigation system will not turn on.

- Illumination does not illuminate.

- Combination meter does not operate.

- A/C does not operate.

- VDC does not operate.

- EyeSight does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.
1.

Turn the ignition switch to ON.

2.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B562) No. 7 (+) — Chassis ground (−):

(B562) No. 14 (+) — Chassis ground (−):

Is the voltage 10 V or more?

2

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal output of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal output of ch2.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 output from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A25 DC/DC CONVERTER 1 CIRCUIT 1 TEMPERATURE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio or navigation system is reset.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

2

2. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC other than P1A25 and P1A26 displayed?

Perform the diagnosis according to DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK DTC.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC P1A25 or P1A26 displayed?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal temperature of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal temperature of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 temperature from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A26 DC/DC CONVERTER 1 CIRCUIT 2 TEMPERATURE

Refer to “DTC P1A25” for diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A25 DC/DC CONVERTER 1 CIRCUIT 1 TEMPERATURE

1. OUTLINE OF DIAGNOSIS

- Detect abnormal temperature of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects abnormal temperature of ch2.

2. EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

3. DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 temperature from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A27 DC/DC CONVERTER 1 INTERNAL CIRCUIT
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio, navigation system or combination meter is reset.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

2

2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

2

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the DC/DC converter 1.

- Judge as NG when the DC/DC converter 1 detects internal malfunction.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Internal malfunction from DC/DC converter 1 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A28 DC/DC CONVERTER 2 BOOST PERFORMANCE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Irregular skipping occurs in audio at restart of Auto Start Stop.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK FOR ANY OTHER DTC ON DISPLAY.
yes

Perform the instructed procedures.

no

2

2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK FOR ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Perform the diagnosis according to DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the DC/DC converter 2 at boosting.

- Judge as NG when the DC/DC converter 2 detects malfunction at boosting.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Malfunction at boosting from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A29 DC/DC CONVERTER 2 INPUT 1 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Sound does not come from audio.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.

Turn the ignition switch to ON, and turn on the audio or navigation system.

Is it powered on?

3

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 2.

Measure the voltage between DC/DC converter 2 and chassis ground.

Connector & terminal

(B629) No. 1 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal input of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal input of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 input from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2A DC/DC CONVERTER 2 INPUT 2 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Sound does not come from audio.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.
1.

Start the engine.

2.

Check the combination meter condition.

Does the combination meter operate normally?

3

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 2.

Measure the voltage between DC/DC converter 2 and chassis ground.

Connector & terminal

(B629) No. 4 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal input of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal input of ch2.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 input from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2B DC/DC CONVERTER 2 OUTPUT 1 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Sound does not come from audio.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK VEHICLE CONDITION.
yes

3

no

2

2. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK VEHICLE CONDITION.

Turn the ignition switch to ON, and turn on the audio or navigation system.

Is it powered on?

3

2

2. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 2.

Measure the voltage between DC/DC converter 2 and chassis ground.

Connector & terminal

(B629) No. 3 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

3. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal output of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal output of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 output from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2C DC/DC CONVERTER 2 OUTPUT 2 VOLTAGE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- Sound does not come from audio.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 2.
no

Perform the instructed procedures.

yes
2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 2.
1.

Turn the ignition switch to ON.

2.

Measure the voltage between DC/DC converter 2 and chassis ground.

Connector & terminal

(B629) No. 6 (+) — Chassis ground (−):

Is the voltage 10 V or more?

2

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal output of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal output of ch2.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 output from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2D DC/DC CONVERTER 2 CIRCUIT 1 TEMPERATURE
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

- Auto Start Stop does not operate.

- When the Auto Start Stop restarts, the audio or navigation system is reset.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

2

2. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is a DTC other than P1A2D and P1A2E displayed?

Perform the diagnosis according to DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK DTC.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is P1A2D or P1A2E displayed?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect abnormal temperature of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal temperature of ch1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch1 temperature from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2E DC/DC CONVERTER 2 CIRCUIT 2 TEMPERATURE

Refer to “DTC P1A2D” for diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1A2D DC/DC CONVERTER 2 CIRCUIT 1 TEMPERATURE

1. OUTLINE OF DIAGNOSIS

- Detect abnormal temperature of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects abnormal temperature of ch2.

2. EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

3. DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Abnormal ch2 temperature from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1A2F DC/DC CONVERTER 2 INTERNAL CIRCUIT
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

2

2. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Start the engine.

3.

Turn the ignition switch to OFF and wait for 10 seconds.

4.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 3) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

2

2. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

Do not release the brake pedal to prevent sudden acceleration of the vehicle.

3.

Operate the Auto Start Stop cancel switch to restart the engine.

4.

Turn the ignition switch to OFF and wait for 10 seconds.

5.

Using the Subaru Select Monitor, read the DTC after repeating the procedure from step 2) to 4) two times. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is the same DTC as current diagnosis output?

Check for the poor contact of DC/DC converter 2 connector. Replace the DC/DC converter 2 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect malfunction of the DC/DC converter 2.

- Judge as NG when the DC/DC converter 2 detects internal malfunction.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
Internal malfunction from DC/DC converter 2 | Reception

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P1C00 BATTERY MONITOR MODULE "A" PERFORMANCE

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

For diagnostic procedure, refer to “DTC P1C00” in “Engine (Diagnostics)”. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P1C00 BATTERY MONITOR MODULE "A" PERFORMANCE

1. OUTLINE OF DIAGNOSIS

- Detect malfunction of the battery status sensor.

- Judge as NG when the ECM detects malfunction of the battery status sensor.

2. EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 1 s or more

3. DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Battery sensor performance] | Malfunction

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P257E ENGINE HOOD SWITCH CIRCUIT LOW
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DATA MONITOR.
no

3

yes
2. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

5

3. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (OPEN SIDE) CONNECTOR.
no

Perform the instructed procedures.

yes
4. CHECK HOOD SWITCH (OPEN SIDE) CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

5. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (CLOSED SIDE) CONNECTOR.
no

Perform the instructed procedures.

yes
6. CHECK HOOD SWITCH (CLOSED SIDE) CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DATA MONITOR.
1.

Turn the ignition switch to ON.

2.

Read the data of [Hood SW (Hood Open Status)] with the front hood closed using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [OFF] displayed in [Hood SW (Hood Open Status)]?

2

3

2. CHECK DATA MONITOR.
1.

Read the data of [Hood SW (Hood Close Status)] with the front hood opened using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [OFF] displayed in [Hood SW (Hood Close Status)]?

The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

5

3. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (OPEN SIDE) CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector of body integrated unit.

3.

Disconnect the connector of hood switch.

4.

Measure the resistance between body integrated unit connector and chassis ground.

Connector & terminal

(i81) No. 7 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Repair the ground short circuit of harness between body integrated unit and hood switch (open side) connector.

4. CHECK HOOD SWITCH (OPEN SIDE) CONNECTOR.
1.

Connect all connectors.

2.

Check continuity in hood switch (open side) connector.

Connector & terminal

(B329) No. 3 — (B329) No. 2:

Is there continuity when the front hood is closed?

Replace the front hood lock assembly. SECURITY AND LOCKS>Front Hood Lock Assembly

Check for poor contact of the body integrated unit connector and hood switch (open side) connector. If there is no abnormality, replace the body integrated unit. SECURITY AND LOCKS>Body Integrated Unit

5. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (CLOSED SIDE) CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector of body integrated unit.

3.

Disconnect the connector of hood switch.

4.

Measure the resistance between body integrated unit connector and chassis ground.

Connector & terminal

(B281) No. 3 — Chassis ground:

Is the resistance 1 MΩ or more?

6

Repair the ground short circuit of harness between body integrated unit and hood switch (closed side) connector.

6. CHECK HOOD SWITCH (CLOSED SIDE) CONNECTOR.
1.

Connect all connectors.

2.

Check continuity in the hood switch (closed side) connector.

Connector & terminal

(B329) No. 1 — (B329) No. 2:

Is there continuity when the front hood is open?

Replace the front hood lock assembly. SECURITY AND LOCKS>Front Hood Lock Assembly

Check for poor contact of the body integrated unit connector and hood switch (closed side) connector. If there is no abnormality, replace the body integrated unit. SECURITY AND LOCKS>Body Integrated Unit

General description
OUTLINE OF DIAGNOSIS

- Detect ON stuck in the hood switch and GND-output short in the hood switch circuit.

- Judge as NG when both two hood switch signals are ON.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P257F ENGINE HOOD SWITCH CIRCUIT HIGH
1. —

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK FOR ANY OTHER DTC ON DISPLAY.
yes

Perform the instructed procedures.

no

2

2. CHECK DATA MONITOR.
no

4

yes
3. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no

6

4. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (CLOSED SIDE) CONNECTOR.
no

Perform the instructed procedures.

yes
5. CHECK HOOD SWITCH (CLOSED SIDE) CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

6. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (OPEN SIDE) CONNECTOR.
no

Perform the instructed procedures.

yes
7. CHECK HOOD SWITCH (OPEN SIDE) CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK FOR ANY OTHER DTC ON DISPLAY.

Turn the ignition switch to ON and wait for 40 seconds.

Is B1012 displayed?

Perform the diagnosis according to DTC. BODY CONTROL(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1012 BATTERY BACKUP POWER SUPPLY

2

2. CHECK DATA MONITOR.

Read the data of [Hood SW (Hood Close Status)] with the front hood closed using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [ON] displayed in [Hood SW (Hood Close Status)]?

3

4

3. CHECK DATA MONITOR.

Read the data of [Hood SW (Hood Open Status)] with the front hood opened using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

Is [ON] displayed in [Hood SW (Hood Open Status)]?

The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

6

4. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (CLOSED SIDE) CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector of body integrated unit.

3.

Disconnect the connector of hood switch.

4.

Measure the resistance between the body integrated unit connector and hood switch connector.

Connector & terminal

(B281) No. 3 — (B329) No. 1:

Is the resistance less than 1 Ω?

5

Repair the open circuit of harness between body integrated unit and hood switch (closed side) connector.

5. CHECK HOOD SWITCH (CLOSED SIDE) CONNECTOR.
1.

Connect all connectors.

2.

Check continuity in the hood switch (closed side) connector.

Connector & terminal

(B329) No. 1 — (B329) No. 2:

Is there continuity when the front hood is closed?

Check for poor contact of the body integrated unit connector and hood switch (closed side) connector. If there is no abnormality, replace the body integrated unit. SECURITY AND LOCKS>Body Integrated Unit

Replace the front hood lock assembly. SECURITY AND LOCKS>Front Hood Lock Assembly

6. CHECK HARNESS BETWEEN BODY INTEGRATED UNIT AND HOOD SWITCH (OPEN SIDE) CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector of body integrated unit.

3.

Disconnect the connector of hood switch.

4.

Measure the resistance between the body integrated unit connector and hood switch connector.

Connector & terminal

(i81) No. 7 — (B329) No. 3:

Is the resistance less than 1 Ω?

7

Repair the open circuit of harness between body integrated unit and hood switch (open side) connector.

7. CHECK HOOD SWITCH (OPEN SIDE) CONNECTOR.
1.

Connect all connectors.

2.

Check continuity in hood switch (open side) connector.

Connector & terminal

(B329) No. 3 — (B329) No. 2:

Is there continuity when the front hood is open?

Check for poor contact of the body integrated unit connector and hood switch (open side) connector. If there is no abnormality, replace the body integrated unit. SECURITY AND LOCKS>Body Integrated Unit

Replace the front hood lock assembly. SECURITY AND LOCKS>Front Hood Lock Assembly

General description
OUTLINE OF DIAGNOSIS

- Detect OFF stuck in the hood switch and short circuit to power supply or open circuit of the hood switch circuit.

- Judge as NG when both two hood switch signals are OFF.

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0128 LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0128 LOST COMMUNICATION WITH PARK BRAKE CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0131 LOST COMMUNICATION WITH POWER STEERING CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0131 LOST COMMUNICATION WITH POWER STEERING CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0140 LOST COMMUNICATION WITH BODY CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0140 LOST COMMUNICATION WITH BODY CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0164 LOST COMMUNICATION WITH HVAC CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0164 LOST COMMUNICATION WITH HVAC CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0401 INVALID DATA RECEIVED FROM ECM/PCM "A"

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0401 INVALID DATA RECEIVED FROM ECM/PCM "A"

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0417 INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0417 INVALID DATA RECEIVED FROM PARK BRAKE CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0420 INVALID DATA RECEIVED FROM POWER STEERING CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0420 INVALID DATA RECEIVED FROM POWER STEERING CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0422 INVALID DATA RECEIVED FROM BODY CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0422 INVALID DATA RECEIVED FROM BODY CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0423 INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUSTER CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0423 INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUSTER CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U0424 INVALID DATA RECEIVED FROM HVAC CONTROL MODULE

For the diagnostic procedure, refer to “TRANSMISSION (DIAGNOSTICS)”. TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0424 INVALID DATA RECEIVED FROM HVAC CONTROL MODULE

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U1604 LOST COMMUNICATION WITH DC/DC CONVERTER MODULE 1
1. —

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

- Use the check board when measuring the ECM terminal voltage and resistance.

- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

1. CHECK DTC.
yes

Perform the instructed procedures.

no

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND CHASSIS GROUND.
no

Perform the instructed procedures.

yes
5. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.

Read the DTC of [Engine] using the Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

Is DTC U0077 displayed?

Perform the diagnosis according to the DTC. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0077 LIN COMMUNICATION BUS "ECM/PCM" OFF

2

2. CHECK HARNESS BETWEEN ECM AND DC/DC CONVERTER 1.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ECM connector.

3.

Disconnect the DC/DC converter 1 connector.

4.

Measure the resistance between ECM connector and DC/DC converter 1 connector.

Connector & terminal

(B134) No. 17 — (B562) No. 9:

Is the resistance less than 1 Ω?

3

Repair the open circuit in harness between ECM connector and DC/DC converter 1 connector.

3. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
1.

Turn the ignition switch to ON. (With the connector disconnected)

2.

Measure the voltage between DC/DC converter 1 connector and chassis ground.

Connector & terminal

(B562) No. 12 (+) — Chassis ground (−):

Is the voltage 12 V or more?

4

Repair the open harness or broken fuse of power supply circuit.

4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND CHASSIS GROUND.
1.

Turn the ignition switch to OFF.

2.

Measure the resistance between DC/DC converter 1 connector and chassis ground.

Connector & terminal

(B563) No. 4 — Chassis ground:

Is the resistance less than 5 Ω?

5

Repair the open circuit of harness between DC/DC converter 1 connector and chassis ground.

5. CHECK REPEATABILITY.
1.

Using the Subaru Select Monitor, perform the clear memory. COMMON(diag)>Clear memory

2.

Execute the inspection mode. AUTO START STOP (DIAGNOSTICS)>Inspection Mode

Is DTC U1604 displayed?

Check for the poor contact in DC/DC converter 1 connector and ECM connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

General description
OUTLINE OF DIAGNOSIS

- Detect the malfunction of the DC/DC converter 1 and open or short circuit in LIN communication lines for DC/DC converter 1.

- Judge as NG when there is no normal LIN communication with DC/DC converter 1.

EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 9 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
DC/DC converter 1 | Data not received (communication failure)

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC U1712 LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR MODULE

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure

For diagnostic procedure, refer to “DTC U1712” in “Engine (Diagnostics)”. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1712 LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR MODULE

1. OUTLINE OF DIAGNOSIS

- Detect LIN communication failure of battery sensor.

- Judge as NG when the ECM detects LIN communication failure of the battery sensor.

2. EXECUTION CONDITION

Secondary parameters | Execution condition
CAN communication | Normal
After IG ON | 1 s or more
[System Voltage(Auto Start Stop)] | 10.5 V or more

3. DIAGNOSTIC METHOD

Judge as NG when the following conditions are established.

Judgment value

Malfunction Criteria | Threshold Value
[Communication state with Battery Sensor] | Malfunction

Time needed for diagnosis: 0.5 s

AUTO START STOP (DIAGNOSTICS) > Autostart Cancel Code(S) Display
OPERATION
1. HOW TO READ AUTOSTART CANCEL CODES
1.

On [Start] screen, select [Diagnosis].

2.

On [Vehicle selection] screen, enter vehicle information and select [OK].

3.

On [Main Menu] screen, select [Each System].

4.

On [Select System] screen, select [Transmission Control System].

5.

On [Select Function] screen, select [Cancel Code].

6.

On [Cancel Code items] screen, select [Autostart cancel Code(s) Display].

- For detailed operation procedures, refer to “Help” of application.

- For details on autostart cancel codes, refer to List of Autostart Cancel Code.

2. LIST OF AUTOSTART CANCEL CODE

Autostart cancel code | Item | Contents of diagnosis | Note | Reference
03 | Hood open | Detected that the front hood lock is released during Auto Start Stop operation. | Front hood lock is released during Auto Start Stop operation. Front hood lock SW is faulty Front hood lock SW circuit harness is open or there is a poor contact of connector | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 03 Hood open
06 | Start failure | Starting failure is detected when the system restarts the engine. | Starter motor is faulty Fuel pump is faulty Fuel injector circuit is faulty | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 06 Startability Malfunction
07 | Starting circuit failure | Detected that the engine does not rotate when the system restarts the engine. | Starter motor is faulty Restart circuit relay malfunction, open or short circuit of harness, poor contact of connector (starter relay, starter cut relay) | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 07 Starter Circuit Failure
08 | AVH brake pressure intensification | Vehicle started to move while the AVH system stops the vehicle during Auto Start Stop operation, so an emergent intensification of brake pressure was performed. | Emergent intensification of brake pressure | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 08 AVH Brake Intensify Press
09 | EyeSight malfunction∗ | EyeSight malfunction is detected while the EyeSight system automatically stops the vehicle and during Auto Start Stop operation. | EyeSight system failure | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 09 EyeSight Failure
0A | CAN communication failure∗ | CAN communication error is detected while the EyeSight system automatically stops the vehicle and during Auto Start Stop operation. | CAN communication error | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 0A CAN Communication Failure
0B | CAN communication failure (engine CM) | CAN communication error is detected in ECM during Auto Start Stop. | CAN communication error in ECM | AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>INSPECTION > 0B ECM CAN Communication Failure

∗ Only for model with EyeSight

- To clear the autostart cancel codes, clear the memory using Subaru Select Monitor. COMMON(diag)>Clear memory

- Up to five autostart cancel codes can be stored. If five or more autostart cancel codes occur, codes will be deleted from the oldest one.

- If autostart cancel codes are not stored, the ignition switch may have been quickly turned from OFF to ON during Auto Start Stop. Or, it is possible that temporary poor contact occurs in the ignition power supply circuit.

- Autostart cancel code 03 will be stored even when canceled by the user operation. Check the time of occurrence and time stamp by interviewing customers.

- Autostart cancel codes 06 and 07 will be stored when the restart cannot be activated by the system during Auto Start Stop.

  If autostart cancel codes are not stored, perform reading of the DTCs of TCM to check if DTC P0604, P0605 and P0613 are displayed. TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC) Also perform reading of the ECM diagnostic codes to check if DTC P1603 and DTC P1604 are displayed. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

  When any DTC is detected, perform the diagnosis according to the DTC. TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)>LIST

  If DTC is not detected, a temporary poor contact of the battery terminal, TCM connector or ECM connector may be the cause.

AUTO START STOP (DIAGNOSTICS) > Autostart Cancel Code(S) Display
INSPECTION
1. 03 Hood open

Detecting condition:

- When the front hood lock is released during Auto Start Stop operation by the user.

- When a malfunction occurs related to the hood SW during the Auto Start Stop.

Trouble symptom:

Buzzer sounds and the Auto Start Stop is canceled.

1. INTERVIEW CUSTOMERS.
no

3

yes
2. INTERVIEW CUSTOMERS.
yes

Perform the instructed procedures.

no

3

3. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. INTERVIEW CUSTOMERS.

Check if the hood opener lever is operated during Auto Start Stop.

Is the hood opener lever is operated?

2

3

2. INTERVIEW CUSTOMERS.

Check when the trouble occurred.

Does it match the time stamp? COMMON(diag)>Time Stamp

Normal.

Cancel code is recorded by the user operation.

3

3. CHECK DTC.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Check for poor contact of the body integrated unit connector and hood switch connector. When there is no failure, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

2. 06 Startability Malfunction

Detecting condition:

When starting failure is detected when the engine is restarted.

Trouble symptom:

After the engine stops, a buzzer sounds and the Auto Start Stop is canceled.

1. CHECK ENGINE START FAILURE.
no

Perform the instructed procedures.

yes
2. CHECK Auto Start Stop STATUS.
yes

Perform the instructed procedures.

no

3

3. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK ENGINE START FAILURE.

Start the engine using the ignition key or push button ignition switch.

Does the engine start?

2

Inspect according to the general diagnosis table. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostics with Phenomenon

2. CHECK Auto Start Stop STATUS.
1.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

Operate the Auto Start Stop cancel switch to restart the engine.

Does the engine start?

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

3

3. CHECK DTC.

Read the DTC of [Engine] using the Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)>LIST

Inspect according to the general diagnosis table. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostics with Phenomenon

3. 07 Starter Circuit Failure

Detecting condition:

When judging that the engine does not start running when the engine is restarted.

Trouble symptom:

After the engine stops, a buzzer sounds and the Auto Start Stop is canceled.

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

1. CHECK ENGINE START FAILURE.
no

Perform the instructed procedures.

yes
2. CHECK Auto Start Stop STATUS.
yes

4

no

3

3. CHECK Auto Start Stop STATUS.
no

Perform the instructed procedures.

yes
4. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK ENGINE START FAILURE.

Start the engine using the ignition key or push button ignition switch.

Does the engine start?

2

Inspect according to the general diagnosis table. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostics with Phenomenon

2. CHECK Auto Start Stop STATUS.
1.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

Operate the Auto Start Stop cancel switch to restart the engine.

Does the starter motor operate?

4

3

3. CHECK Auto Start Stop STATUS.
1.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

Read the data of [ECM Restart Request Signal State] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

3.

Operate the Auto Start Stop cancel switch to restart the engine.

Does the display of [ECM Restart Request Signal State] change to ON at restarting?

4

Check the harness between TCM connector and ECM connector.

(T10) No. 23 — (E158) No. 36

4. CHECK DTC.

Read the DTC of [Engine] using the Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)>LIST

Inspect according to the general diagnosis table. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostics with Phenomenon

4. 08 AVH Brake Intensify Press

Refer to the List of Autostart Cancel Code. AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>OPERATION > LIST OF AUTOSTART CANCEL CODE

5. 09 EyeSight Failure

Detecting condition:

When EyeSight malfunction is detected while the EyeSight system automatically stops the vehicle and during Auto Start Stop operation.

Trouble symptom:

Buzzer sounds and the Auto Start Stop is canceled.

1. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.

Using the Subaru Select Monitor, read DTC of the EyeSight system. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Perform the diagnosis for the EyeSight system. EyeSight (DIAGNOSTICS)>Basic Diagnostic Procedure

6. 0A CAN Communication Failure

Detecting condition:

When CAN communication error is detected while the EyeSight system automatically stops the vehicle and during Auto Start Stop operation.

Trouble symptom:

Buzzer sounds and the Auto Start Stop is canceled.

1. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.

Read the DTC using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Perform the diagnosis for LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

7. 0B ECM CAN Communication Failure

Detecting condition:

When CAN communication error is detected in ECM during Auto Start Stop control.

Trouble symptom:

Buzzer sounds and the Auto Start Stop is canceled.

1. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK DTC.

Read the DTC of [Engine] using the Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)>LIST

Perform the diagnosis for LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

AUTO START STOP (DIAGNOSTICS) > Diagnostics with Phenomenon
INSPECTION
1. TROUBLE SYMPTOM

Trouble symptom | Note
Symptom 1: Engine does not stop. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 1: ENGINE DOES NOT STOP
Symptom 2: The engine stop period is short. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 2: THE ENGINE STOP PERIOD IS SHORT
Symptom 3: After the engine stops, a buzzer sounds and the Auto Start Stop is canceled. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 3: AFTER THE ENGINE STOPS, A BUZZER SOUNDS AND THE Auto Start Stop IS CANCELED
Symptom 4: The value of [Voltage drop prohibition evaluation at the time of start] in “Data Monitor” is [Not Permit]. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 4: THE VALUE OF VOLTAGE DROP PROHIBITION EVALUATION AT THE TIME OF STARTOFF
Symptom 5: Engine does not start after stop. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 5: ENGINE DOES NOT START AFTER STOP
Symptom 6: Auto A/C, navigation system or audio does not operate. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 6: AUTO A/C, NAVIGATION SYSTEM OR AUDIO DOES NOT OPERATE
Symptom 7: Auto A/C or combination meter does not operate. | AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > SYMPTOM 7: AUTO A/C OR COMBINATION METER DOES NOT OPERATE

2. SYMPTOM 1: ENGINE DOES NOT STOP

Probable defective cause:

- Judged the vehicle status as “Auto Start Stop conditions are not met”.

- One of Auto Start Stop conditions is not established.

For Auto Start Stop conditions, refer to “Data Monitor”. AUTO START STOP (DIAGNOSTICS)>Data Monitor

1. CHECK Auto Start Stop INDICATOR.
no

Perform the instructed procedures.

yes
2. CHECK DTC.
yes

Perform the instructed procedures.

no

3

3. CHECK Auto Start Stop.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK Auto Start Stop INDICATOR.

Check the illumination status of Auto Start Stop indicator. AUTO START STOP (DIAGNOSTICS)>Auto Start Stop Indicator>CONDITION CHECK

Is the illumination status of Auto Start Stop indicator OK?

2

Check the Auto Start Stop indicator. AUTO START STOP (DIAGNOSTICS)>Auto Start Stop Indicator>Auto Start Stop INDICATOR DOES NOT ILLUIMINATE OR REMAINS ON

2. CHECK DTC.
1.

Start the engine.

2.

Using the Subaru Select Monitor, read all DTCs. COMMON(diag)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC.

3

3. CHECK Auto Start Stop.
1.

Start the engine.

2.

Warm up the engine until engine coolant temperature is higher than 75°C (167°F) and ATF temperature higher than 50°C (122°F).

3.

Turn off all the electric load.

4.

Check that the hood is closed.

5.

Drive the vehicle at 40 km/h (24.9 MPH) or more, and then stop the vehicle at a level and safe place with the steering wheel in straight direction.

6.

Depress the brake pedal firmly.

Does Auto Start Stop operate?

- The vehicle has returned to a normal condition at this time.

- Auto Start Stop operation condition may have not been established for a moment.

Check the appropriate items using the list of check items classified by symptoms. AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > LIST OF CHECK ITEMS CLASSIFIED BY SYMPTOMS

3. SYMPTOM 2: THE ENGINE STOP PERIOD IS SHORT

The engine stop period due to Auto Start Stop is the maximum of 120 seconds.

Probable defective cause:

- The battery voltage dropped during Auto Start Stop (state where electrical load is large, battery capacity is low, or battery was degraded).

- Judged the vehicle status as “Auto Start Stop restart conditions are met” (air conditioning gets worse in the vehicle during A/C operation).

- Judged that “the user operates the restart procedure” (braking or steering operation, etc.).

Diagnostic procedure:

1.

Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. AUTO START STOP (DIAGNOSTICS)>Active Test

2.

While stopping the engine using Auto Start Stop, check the appropriate items using the list of check items classified by symptoms. AUTO START STOP (DIAGNOSTICS)>Diagnostics with Phenomenon>INSPECTION > LIST OF CHECK ITEMS CLASSIFIED BY SYMPTOMS

4. SYMPTOM 3: AFTER THE ENGINE STOPS, A BUZZER SOUNDS AND THE Auto Start Stop IS CANCELED

During Auto Start Stop, if the engine starting is prohibited for safety, the Auto Start Stop function is canceled and autostart cancel code is stored in the TCM. After the Auto Start Stop is canceled, the vehicle can be started with the ignition key or push button ignition switch.

Probable defective cause:

Judged the vehicle status as “Auto Start Stop restart cancel conditions are met”.

Diagnostic procedure:

Check the appropriate item using the “List of Autostart Cancel Code”. AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>OPERATION > LIST OF AUTOSTART CANCEL CODE

5. SYMPTOM 4: THE VALUE OF [Voltage drop prohibition evaluation at the time of start] IN “DATA MONITOR” IS [OFF]

Probable defective cause:

- Battery other than the genuine battery for Auto Start Stop is installed.

- Non-genuine electrical parts are installed (electric load is large).

- Battery internal resistance has increased (battery deterioration or battery capacity decrease).

Clear the memory after repairing or replacing the faulty part. COMMON(diag)>Clear memory

1. CHECK BATTERY.
no

2

yes
2. CHECK ELECTRICAL PARTS ATTACHED TO VEHICLE.
no

3

yes
3. CHECK REPEATABILITY.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK BATTERY.

Is the vehicle equipped with the genuine battery for Auto Start Stop?

2

Install the genuine battery for Auto Start Stop. STARTING/CHARGING SYSTEMS(H4DO)>Battery After operation 2

2. CHECK ELECTRICAL PARTS ATTACHED TO VEHICLE.

Is the vehicle equipped with non-genuine electrical parts?

Remove the non-genuine electrical parts 3

3

3. CHECK REPEATABILITY.
1.

Turn the ignition switch to OFF, and wait for 10 seconds or more.

2.

Turn the ignition switch to ON.

3.

Read the data of [Voltage drop prohibition evaluation at the time of start] using Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Data Monitor

4.

Start the engine, and repeat the engine stop and restart operation using Auto Start Stop for 10 times or more.

While repeating the engine stop and restart operation, does the display of [Voltage drop prohibition evaluation at the time of start] change to [OFF]?

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery

- The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

- In this case, temporary functional decline of battery, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

6. SYMPTOM 5: ENGINE DOES NOT START AFTER STOP

Probable defective cause:

- Starter circuit failure

- Engine trouble

- Judged the vehicle status as “Auto Start Stop restart cancel conditions are met”.

1. CHECK AUTOSTART CANCEL CODE.
yes

Perform the instructed procedures.

no

2

2. CHECK DTC.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK AUTOSTART CANCEL CODE.

Check the autostart cancel code. AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display

Is autostart cancel code stored?

Check the appropriate item using the “List of Cancel Codes”. AUTO START STOP (DIAGNOSTICS)>Autostart Cancel Code(S) Display>OPERATION > LIST OF AUTOSTART CANCEL CODE

2

2. CHECK DTC.

Read the DTC of [Engine] using the Subaru Select Monitor. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. ENGINE (DIAGNOSTICS)(H4DO)>Diagnostic Trouble Code (DTC)>LIST

The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

7. SYMPTOM 6: AUTO A/C, NAVIGATION SYSTEM OR AUDIO DOES NOT OPERATE

Probable defective cause:

- Open circuit or short circuit to ground of DC/DC converter 1 power supply circuit

- Open circuit or short circuit to ground in harness between DC/DC converter 1 and fuse holder

- Open circuit or short circuit to ground in harness between fuse holder and each electrical part

- Blown out of fuse

- Poor contact of DC/DC converter 1 connector

- Faulty DC/DC converter 1

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

1. CHECK FUSE.
yes

Perform the instructed procedures.

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND FUSE HOLDER.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK FUSE.

Check the fuse located on the circuit of (B563) No. 5.

Is the fuse blown out?

- Check the following item and repair or replace if necessary.

  - Short circuit to ground in harness between fuse holder and each electrical part

  - Blown out of fuse

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
1.

Turn the ignition switch to ON.

2.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B563) No. 5 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair or replace if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

  - Short circuit to ground in harness between DC/DC converter 1 and fuse holder

3. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B562) No. 14 (+) — Chassis ground (−):

(B562) No. 7 (+) — Chassis ground (−):

(B562) No. 8 (+) — Chassis ground (−):

Is the voltage 10 V or more?

4

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND FUSE HOLDER.
1.

Turn the ignition switch to OFF.

2.

Disconnect the DC/DC converter 1 connector.

3.

Measure the resistance in harness between DC/DC converter 1 connector and fuse holder.

Connector & terminal

(B562) No. 14 — Fuse holder:

(B562) No. 7 — Fuse holder:

(B562) No. 8 — Fuse holder:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between fuse holder and each electrical part. If the malfunction is not solved, perform the diagnosis for each electrical part.

Repair the open circuit of harness between DC/DC converter 1 and fuse holder.

8. SYMPTOM 7: AUTO A/C OR COMBINATION METER DOES NOT OPERATE

Probable defective cause:

- Open circuit or short circuit to ground of DC/DC converter 1 power supply circuit

- Open circuit or short circuit to ground in harness between DC/DC converter 1 and fuse holder

- Open circuit or short circuit to ground in harness between fuse holder and each electrical part

- Blown out of fuse

- Poor contact of DC/DC converter 1 connector

- Faulty DC/DC converter 1

Wiring diagram:

Auto Start Stop WIRING SYSTEM>Auto Start Stop

1. CHECK FUSE.
yes

Perform the instructed procedures.

no

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
3. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.
no

Perform the instructed procedures.

yes
4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND FUSE HOLDER.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK FUSE.

Check the fuse located on the circuit of (B563) No. 3.

Is the fuse blown out?

- Check the following item and repair or replace if necessary.

  - Short circuit to ground in harness between fuse holder and each electrical part

  - Blown out of fuse

2

2. CHECK INPUT VOLTAGE OF DC/DC CONVERTER 1.
1.

Turn the ignition switch to ON.

2.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B563) No. 3 (+) — Chassis ground (−):

Is the voltage 10 V or more?

3

- Check the following item and repair or replace if necessary.

  - Open or short to ground in harness of power supply circuit

  - Blown out of fuse

  - Short circuit to ground in harness between DC/DC converter 1 and fuse holder

3. CHECK OUTPUT VOLTAGE OF DC/DC CONVERTER 1.

Measure the voltage between DC/DC converter 1 and chassis ground.

Connector & terminal

(B562) No. 14 (+) — Chassis ground (−):

(B562) No. 7 (+) — Chassis ground (−):

(B562) No. 8 (+) — Chassis ground (−):

Is the voltage 10 V or more?

4

Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. STARTING/CHARGING SYSTEMS(H4DO)>Auto Start Stop DC/DC Converter

4. CHECK HARNESS BETWEEN DC/DC CONVERTER 1 AND FUSE HOLDER.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector from the DC/DC converter 1.

3.

Measure the resistance in harness between DC/DC converter 1 and fuse holder.

Connector & terminal

(B562) No. 14 — Fuse holder:

(B562) No. 7 — Fuse holder:

(B562) No. 8 — Fuse holder:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between fuse holder and each electrical part. If the malfunction is not solved, perform the diagnosis for each electrical part.

Repair the open circuit of harness between DC/DC converter 1 and fuse holder.

9. LIST OF CHECK ITEMS CLASSIFIED BY SYMPTOMS

- Perform the diagnosis by comparing the vehicle’s data monitor with each condition of Auto Start Stop. AUTO START STOP (DIAGNOSTICS)>Data Monitor

- Each signal check includes the harness condition check and connector condition check.

Check target | Display | Judging item | Check item
Symptom 1 | Symptom 2
|  | ECM Idle Stop Prohibition | Judgment of prohibited condition by ECM | ECM CAN communication condition
|  | Low water temperature stop prohibition judgment Coolant Temp. | Judgment that engine coolant temperature is low | Engine coolant temperature sensor signal ECM input judgment CAN communication condition
|  | Battery current prohibition judgment Battery Charge/Discharge Current | Judgment that electric load is large | Battery sensor signal ECM input judgment CAN communication condition
|  | Battery high temperature prohibition judgment Battery low temperature prohibition judgment Estimated Battery Temperature | Judgment that battery temperature is high or low | Battery sensor signal ECM input judgment CAN communication condition
|  | Brake vacuum restart request evaluation Brake Booster Relative Pressure | Judgment that brake booster vacuum pressure is insufficient | Brake booster Brake booster pressure sensor output signal VDC CM input judgment CAN communication condition
|  | Prohibition judgment by the atmospheric pressure condition Atmosphere Pressure | Judgment that altitude is high | Manifold absolute pressure sensor signal ECM input judgment CAN communication condition
|  | Idle Switch(Accel) | Judgment that accelerator pedal is depressed | Accelerator pedal position sensor signal ECM input judgment CAN communication condition
| — | Engine rotation prohibition judgment Engine Speed(Auto Start Stop) | Judgment that it is idling trouble | Engine speed signal ECM input judgment CAN communication condition
| — | Shift position information | Judgment that select lever is in a range other than “D” | Inhibitor switch signal TCM CAN communication condition
— |  | Shift position information | Judgment that select lever is in “R” range | Inhibitor switch signal TCM CAN communication condition
|  | Vehicle speed restart request evaluation Vehicle Speed | Judgment that the vehicle is traveling | Vehicle speed sensor signal VDC CM input judgment CAN communication condition
|  | Brake fluid pressure | Judgment that brake fluid pressure is insufficient | Pressure sensor signal VDC CM input judgment CAN communication condition
| — | Inclination prohibition judgment Forward and Rearward G | Judgment that road surface inclination is out of condition | Yaw rate & G sensor signal VDC CM input judgment CAN communication condition
| — | (ABS operation, No display) | Judgment that ABS operates before vehicle stops | VDC CM control condition CAN communication condition
|  | Steering angle prohibition judgment Steering angle | Judgment that steering angle is large or steering wheel is being turned | Steering angle sensor signal VDC CM input judgment CAN communication condition
EPS restart request judgment EPS idle stop prohibition | Torque sensor signal Power steering CM input judgment CAN communication condition
|  | A/C Idle Stop Permission Air-conditioning prohibition evaluation Air conditioning restart request evaluation | Judgment of air conditioner prohibition condition | Air conditioner CAN communication condition
| — | Seat Belt Buckle Switch (D Seat Side) | Judgment that driver’s seat belt is not fastened | Seat belt switch signal Combination meter input judgment CAN communication condition
|  | Electric accessories restart request evaluation | Judgment of prohibited condition of turn signal or wiper | Auto Start Stop customize setting condition
Turn signal evaluation | Turn signal light signal Combination meter input judgment CAN communication condition
(Wiper judgment, No display) | Wiper switch signal Body integrated unit input judgment CAN communication condition
|  | Rear Defogger Air-conditioning prohibition evaluation | Judgment that rear defogger is turned on | Rear defogger switch signal Combination meter input judgment Body integrated unit control condition CAN communication condition
| — | Door SW (D Seat Side) | Judgment that driver’s door is opened | Door switch signal Body integrated unit input judgment CAN communication condition
|  | DC/DC Converter Temperature Prohibition Evaluation DC/DC Converter 1 Status | Judgment of sub power supply temperature warning condition | DC/DC converter
| — | Hood open evaluation Hood SW Hood diagnosis signal | Judgment that front hood lock is released | Hood switch signal Body integrated unit input judgment CAN communication condition
|  | Cancel status Auto Start Stop OFF Switch | Judgment of Auto Start Stop cancel switch operation | Auto Start Stop cancel switch signal Combination meter input judgment
|  | Voltage drop prohibition evaluation at the time of start Main power supply voltage | Judgment that voltage decrease is large during starting | Battery (deterioration, capacity decrease) Non-genuine electrical parts (electric load is large) TCM input judgment
|  | Battery protection restart request evaluation Main power supply voltage Audio Supply Voltage | Judgment of prohibited condition of battery protection | Battery (deterioration, capacity decrease) Non-genuine electrical parts (electric load is large) ECM input judgment
Battery Charge/Discharge Current | Battery sensor signal ECM input judgment CAN communication condition
DC/DC Converter 1 Status | DC/DC converter input signal (input terminal voltage)
| — | Engine Speed Complete combustion evaluation Engine stall evaluation Key start completion evaluation | Judgment of engine stop condition | Engine speed signal ECM output judgment
|  | Stop Light Switch | Judgment that brake pedal is released | Stop light switch signal TCM input judgment
|  | EPB Idle stop prohibition EPB restart request judgment | Judgment that electronic parking brake is activated | Electronic parking brake operation status