OCCUPANT DETECTION(DIAGNOSTICS)
OD(diag)

OCCUPANT DETECTION(DIAGNOSTICS) > Basic Diagnostic Procedure
PROCEDURE

1. PERFORM CUSTOMER INTERVIEW.

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

Did you interview the customer?

2

Perform the interview, and 2

2. PERFORM BASIC INSPECTION.

Perform basic inspection. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>INSPECTION

Is the check result OK?

3

Repair the faulty part found in basic inspection, and 3

3. CHECK SUBARU SELECT MONITOR COMMUNICATION.
1.

Turn the ignition switch to OFF.

2.

Connect the Subaru Select Monitor to data link connector. COMMON(diag)>Data Link Connector

3.

Turn the ignition switch to ON and run the Subaru Select Monitor.

4.

Select [Airbag].

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

Is communication possible?

4

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

4. CHECK DTC.

Read the DTC of [Airbag] using the Subaru Select Monitor. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1650, B1655 or B1656 displayed? (Current malfunction)

Record the DTC, and 7

5

5. CHECK SUBARU SELECT MONITOR COMMUNICATION.
1.

Turn the ignition switch to OFF.

2.

Connect the Subaru Select Monitor to data link connector. COMMON(diag)>Data Link Connector

3.

Turn the ignition switch to ON and run the Subaru Select Monitor.

4.

Select [Occupant Detection].

For detailed operation procedures, refer to “Application help”.

Is communication possible?

6

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

6. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed? (Current malfunction)

Record the DTC, and 7

Currently, it is normal.

7. PERFORM DIAGNOSIS.
1.

Perform the diagnosis according to the displayed DTC. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2.

Repair or replace the cause of trouble.

3.

Using the Subaru Select Monitor, perform the clear memory of [Airbag] or [Occupant Detection]. COMMON(diag)>Clear memory

- Airbag

- Occupant Detection

4.

Execute the inspection mode. OCCUPANT DETECTION(DIAGNOSTICS)>Inspection Mode

5.

Using the Subaru Select Monitor, read the DTCs of [Airbag] or [Occupant Detection]. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC) OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

- Airbag

- Occupant Detection

Are any DTCs displayed? (Current malfunction)

Repeat step 7 until DTC is not shown.

Finish the diagnosis.

OCCUPANT DETECTION(DIAGNOSTICS) > Check List for Interview
CHECK

Inspect the following items regarding the vehicle’s state.

Occupant Detection Check List for Interview   Date of Vehicle Bring-in   Year   Month   Day
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 and time when the trouble occurred | Year   Month   Date
Condition of trouble occurrence (How the trouble occurs) | Weather | Fine Cloudy Rainy Snowy Others (     )
Temperature | °C (°F) —    °C (°F)
Vehicle status | Starting Idling Driving Constant speed  km/h (MPH) Acceleration  km/h (MPH) —   km/h (MPH) Deceleration  km/h (MPH) —   km/h (MPH) Turning  km/h (MPH) Other:
Road conditions | Local street Highway Major arterial road Limited highway Other:
Road condition | Flat road Uphill Downhill Gravel road Dry Wet Covered with fresh snow Covered with hardened snow Frozen Other:
Seat slide position |
Seat reclining position |
How often | Always Sometimes times per day times per week times per month Dirt road (only once in the past)
Generation timing | Example: It occurs about 30 minutes after driving.
Accessory installation condition | Child restraint seat ISO FIX Seat belt fixed Other: Passenger’s seat cover Other:
Seat slide operation | Smooth Dragged Does not move Other:
Seat reclining operation | Smooth Dragged Does not move Other:
Situation inside seat back pocket | Heavy object is in (     ) No heavy object is in
Situation around seat | Foreign matter exists (     ) No foreign matter exists
Situation under seat | Foreign matter exists (     ) No foreign matter exists
Airbag warning light status | Normal (After turning the ignition switch to ON, illuminates for approximately 6 seconds and goes off.) Remains ON Remains OFF
Passengers airbag ON/OFF indicator status | Normal (After turning the ignition switch to ON, illuminates for 6 seconds then goes off for 2 seconds, and either ON (adult) or OFF (children/unoccupied) illuminates.) Both remain ON Both remain OFF
Diagnostic trouble code | Airbag | No Yes (     ) Select monitor communication impossible
Occupant Detection | No Yes (     ) Select monitor communication impossible
Trouble condition | Passenger’s airbag indicator indicates OFF even when an adult occupies the passenger’s seat. Passenger’s airbag indicator indicates ON even when a child restraint seat is installed on the passenger’s seat. Other:
Sensor output at empty seat (Data monitor value) When measuring sensor output, adjust the seat to the same position as in system adjustment. | Front left | kg (lb)
Front right | kg (lb)
Rear left | kg (lb)
Rear right | kg (lb)
Total load | kg (lb)
Sensor output at loading an inspection weight (Data monitor value) When measuring sensor output, adjust the seat to the same position as in system adjustment. | Front left | kg (lb)
Front right | kg (lb)
Rear left | kg (lb)
Rear right | kg (lb)
Total load | kg (lb)
Vehicle bring-in history information |

OCCUPANT DETECTION(DIAGNOSTICS) > General Description
CAUTION
1. AIRBAG SYSTEM

Before performing diagnosis, refer to “CAUTION” in “General Description” in AIRBAG SYSTEM. AIRBAG(DIAGNOSTICS)>General Description>CAUTION

2. OCCUPANT DETECTION SYSTEM
1.

When any of the following operation has been done, be sure to perform [Rezeroing] of occupant detection system. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

- Replacing occupant detection system

- Removing and disassembling passenger’s seat

- Loosening passenger’s seat bolt

2.

The load sensor of the occupant detection system (passenger seat only) is fixed to the cushion frame assembly. Never remove the load sensor from the cushion frame assembly.

3.

The cushion pad, cushion cover, occupant detection control module and seat harness can be replaced as a single unit. When the cushion frame assembly is replaced, the occupant detection control module, seat harness and load sensor are assembled. When replacing the cushion frame assembly, do not touch the load sensor to avoid electrical damage.

4.

If the seat cushion cover is removed, make sure to replace the hang wire on the seat cushion side with a new wire.

5.

Never connect the battery in reverse polarity. Occupant detection system may be destroyed instantly.

6.

Do not disconnect the battery cables while the engine is running. A large counter electromotive force will be generated in the generator, and this voltage may damage electronic parts such as occupant detection control module.

7.

Before disconnecting the connectors of each sensor and control module, be sure to turn the ignition switch to OFF and wait for 60 seconds or more. Occupant detection control module may be damaged.

8.

Every occupant detection system-related part is a precision part. Do not drop them.

9.

Do not use electrical test equipment on wiring harness and connector circuits of the airbag system.

10.

Be careful not to damage the airbag system wiring harness when servicing the occupant detection system.

11.

Refer to CAUTION in Airbag System when repairing the occupant detection system. AIRBAG(DIAGNOSTICS)>General Description>CAUTION

OCCUPANT DETECTION(DIAGNOSTICS) > General Description
INSPECTION

Before performing diagnostics, check the following item which might affect occupant detection system problems.

1. BASIC INSPECTION
1.

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery>INSPECTION

2.

Check the main and other fuses, harnesses and connectors. Also check grounding.

OCCUPANT DETECTION(DIAGNOSTICS) > General Description
PREPARATION TOOL

To measure the voltage and resistance of airbag system and occupant detection system components, be sure to use the specified test harness.

1. SPECIAL TOOL

- Subaru Select Monitor

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | — | SUBARU SELECT MONITOR 4 | Used for setting of each function and troubleshooting for electrical system. For detailed operation procedures, refer to “Help” of application.

- TEST HARNESS Y

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299AG040 | TEST HARNESS Y | Used for troubleshooting seat belt buckle switch.

- TEST HARNESS AE

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299XA030 | TEST HARNESS AE | TEST HARNESS Y adapter harness. Used for troubleshooting seat belt buckle switch.

- TEST HARNESS AB

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299XA000 | TEST HARNESS AB | Used when measuring voltage and resistance of occupant detection system.

- TEST HARNESS BB

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299FL020 | TEST HARNESS BB | Used when measuring voltage and resistance of occupant detection system.

- TEST HARNESS BC

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299FL030 | TEST HARNESS BC | Used when measuring voltage and resistance of occupant detection system. Two sets may be required.

- TEST HARNESS BD

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299XC000 (Newly adopted tool) | TEST HARNESS BD | Used when measuring voltage and resistance of airbag control module.

- TEST HARNESS D

  ILLUSTRATION | TOOL NUMBER | DESCRIPTION | REMARKS
  | 98299AG060 | TEST HARNESS D | Used for troubleshooting seat belt buckle switch.

2. GENERAL TOOL

TOOL NAME | REMARKS
Circuit tester | Used for measuring resistance, voltage and current.
DST-i | Used together with Subaru Select Monitor 4.
Inspection weight | Used for sensitivity inspection after Rezero operation. Prepare an inspection weight of 30 to 40 kg in total. If it is a weight of which the accuracy has been verified (within ±0.5%), there is no need of measuring the actual value using a digital scale. The combination of 98399AG000 and 98399AG010 (total weight: 35.812 kg) can be used.
Digital scale | Used only for sensitivity inspection after Rezero operation, using an inspection weight of which the actual weight is not verified or unknown.

OCCUPANT DETECTION(DIAGNOSTICS) > General Description
SYSTEM BLOCK DIAGRAM
OCCUPANT DETECTION(DIAGNOSTICS) > Electrical Component Location
LOCATION

(1) | Airbag ON/OFF indicator |  |  |  |

(1) | Passenger’s seat | (4) | Load sensor 1 (FL) | (6) | Load sensor 2 (FR)
(2) | Buckle switch | (5) | Load sensor 4 (RR) | (7) | Occupant detection control module
(3) | Load sensor 3 (RL) |  |  |  |

OCCUPANT DETECTION(DIAGNOSTICS) > Airbag Connector
PROCEDURE
1. OCCUPANT DETECTION SYSTEM (BETWEEN AIRBAG REAR HARNESS AND SEAT HARNESS)
1.

How to disconnect:

Press the lock arm (A) and disconnect the connector.

When pulling the slide lock or disconnecting connector, be sure to hold the connector, not the harness.

- Back face of passenger’s seat (typical examples shown)

  (A) | Lock arm |  |  |  |
  (1) | Occupant detection control module | (2) | Load sensor |  |

2.

How to connect:

Holding the connector, push it in securely until a clicking sound is heard.

Be sure to insert the connector in until it is locked. Then pull it gently to make sure that it is locked.

2. AIRBAG CONTROL MODULE

Refer to the airbag system section. AIRBAG SYSTEM>Airbag Connector>PROCEDURE > AIRBAG CONTROL MODULE

3. BUCKLE SWITCH (PASSENGER’S SEAT)

Refer to the airbag system section. AIRBAG SYSTEM>Airbag Connector>PROCEDURE > BUCKLE SWITCH RH

OCCUPANT DETECTION(DIAGNOSTICS) > Control Module I/O Signal
ELECTRICAL SPECIFICATION

Terminal No. | Content | Measuring condition | Standard
(AB61) No. 1 (+) ←→ Chassis ground (−) | Battery power supply | Always | Battery voltage
(AB61) No. 2 | Airbag CM communication (+) | — | —
(AB61) No. 3 | Airbag CM communication (−) | — | —
(AB61) No. 4 | — | — | —
(AB61) No. 5 | Buckle switch (−) | — | —
(AB61) No. 6 | — | — | —
(AB61) No. 7 (+) ←→ Chassis ground (−) | Ignition power supply | When ignition switch is ON | Battery voltage
(AB61) No. 8 | — | — | —
(AB61) No. 9 (+) ←→ Chassis ground (−) | Buckle switch (+) | Buckle not engaged → Buckle engaged | 3.8 V — 24 V → 3.8 V — 16V
(AB61) No. 10 | — | — | —
(AB61) No. 11 | — | — | —
(AB61) No. 12 | — | — | —
(AB69) No. 1 | Load sensor 1 (FL) GND | — | —
(AB69) No. 2 | Load sensor 2 (FR) GND | — | —
(AB69) No. 3 | Load sensor 3 (RL) GND | — | —
(AB69) No. 4 | Load sensor 4 (RR) GND | — | —
(AB69) No. 5 | Load sensor 3 (RL) power supply | When ignition switch is ON | 4.9 V — 5.1 V
(AB69) No. 6 | Load sensor 4 (RR) power supply | When ignition switch is ON | 4.9 V — 5.1 V
(AB69) No. 7 | Load sensor 1 (FL) signal | — | —
(AB69) No. 8 | Load sensor 2 (FR) signal | — | —
(AB69) No. 9 | Load sensor 3 (RL) signal | — | —
(AB69) No. 10 | Load sensor 4 (RR) signal | — | —
(AB69) No. 11 (+) ←→ Chassis ground (−) | Load sensor 1 (FL) power supply | When ignition switch is ON | 4.9 V — 5.1 V
(AB69) No. 12 (+) ←→ Chassis ground (−) | Load sensor 2 (FR) power supply | When ignition switch is ON | 4.9 V — 5.1 V

OCCUPANT DETECTION(DIAGNOSTICS) > Inspection Mode
PROCEDURE

Recreate the circumstance by referring to the conditions described in the checklist.

OCCUPANT DETECTION(DIAGNOSTICS) > Warning Light Illumination Pattern
INSPECTION
1. AIRBAG WARNING LIGHT

Refer to AIRBAG (DIAGNOSTICS). AIRBAG(DIAGNOSTICS)>Warning Light Illumination Pattern

2. PASSENGER’S AIRBAG ON/OFF INDICATOR

(1) | Passenger’s airbag ON indicator light | (6) | Light ON | (10) | OFF
(2) | Passenger’s airbag OFF indicator light | (7) | Empty | (11) | ON
(3) | Occupant seating | (8) | Child | (12) | Approx. 6 seconds
(4) | Ignition switch | (9) | Adult | (13) | Approx. 2 seconds
(5) | Light OFF |  |  |  |

OCCUPANT DETECTION(DIAGNOSTICS) > Warning Light Illumination Pattern
WARNING LIGHT DOES NOT ILLUMINATE
1. AIRBAG WARNING LIGHT

Refer to AIRBAG (DIAGNOSTICS). AIRBAG(DIAGNOSTICS)>Warning Light Illumination Pattern

2. PASSENGER’S AIRBAG ON/OFF INDICATOR

Detecting condition:

- Passenger’s airbag ON/OFF indicator malfunction

- Airbag control module to combination meter circuit is shorted or open.

- Grounding circuit is faulty.

- Connector connection is improper.

- Airbag control module is faulty.

- Occupant detection control module is faulty.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. CHECK DTC.

Read the DTC of [Airbag] using the Subaru Select Monitor. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1661 displayed? (Current malfunction)

Perform the diagnosis of DTC B1661.

2

2. CHECK WARNING BOX.

Check for poor contact of the warning box connector.

Is there poor contact of connector?

Repair or replace the poor contact.

3

3. CHECK DTC.

Read the DTC of [Airbag] using the Subaru Select Monitor. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any DTC other than DTC B1661 displayed?

Perform the diagnosis for the displayed DTCs. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

4

4. REZERO.

Perform [Rezero]. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

Does the passenger’s airbag indicator illuminate?

Finish the diagnosis.

Replace the cushion frame assembly. SEATS>Front Seat>DISASSEMBLY

OCCUPANT DETECTION(DIAGNOSTICS) > Warning Light Illumination Pattern
WARNING LIGHT REMAINS ON

For the diagnostic procedures, refer to “WARNING LIGHT DOES NOT COME ON”. OCCUPANT DETECTION(DIAGNOSTICS)>Warning Light Illumination Pattern>WARNING LIGHT DOES NOT ILLUMINATE

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure for Subaru Select Monitor Communication
INSPECTION
1. COMMUNICATION WITH [Airbag] IS IMPOSSIBLE

Detecting condition:

Defective harness connector

Trouble symptom:

Communication is impossible between [Airbag] and Subaru Select Monitor.

Refer to AIRBAG (DIAGNOSTICS). AIRBAG(DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

2. COMMUNICATION WITH [Occupant Detection] IS IMPOSSIBLE

The occupant detection system communicates with the Subaru Select Monitor via the airbag control module.

Detecting condition:

Defective harness connector between airbag control module and occupant detection control module

Trouble symptom:

Communication is impossible between the airbag control module and the occupant detection control module.

Before performing diagnosis, refer to “CAUTION” in “General Description”. AIRBAG(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

1. CHECK SUBARU SELECT MONITOR COMMUNICATION.
1.

Turn the ignition switch to ON.

2.

Using the Subaru Select Monitor, check whether the communication with [Airbag] can be executed normally.

Is communication with [Airbag] possible?

5

2

2. CHECK SUBARU SELECT MONITOR COMMUNICATION.

Using the Subaru Select Monitor, check whether the communication with [Body Control] can be executed normally.

Is communication with [Body Control] possible?

Refer to AIRBAG (DIAGNOSTICS). AIRBAG(DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

3

3. CHECK SUBARU SELECT MONITOR.

Connect the Subaru Select Monitor to another vehicle to check whether the communication can be executed normally.

Does the Subaru Select Monitor communicate?

4

Repair or replace the Subaru Select Monitor.

4. CHECK HARNESS BETWEEN DATA LINK CONNECTOR AND BODY INTEGRATED UNIT.

Check for malfunction in harness between data link connector and body integrated unit on vehicle to be diagnosed.

Is the check result OK?

Replace the body integrated unit. SECURITY AND LOCKS>Body Integrated Unit

Repair or replace the faulty harness.

5. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (OPEN CIRCUIT IN IGNITION POWER SUPPLY).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB61) of occupant detection control module.

3.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

4.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 7 (+) — Chassis ground (−):

Is the voltage 11 V or more?

7

6

6. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (OPEN CIRCUIT IN IGNITION POWER SUPPLY).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB59) of seat harness.

3.

Connect the connector (1AB) in the test harness AB to the connector (AB53).

4.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

5.

Using a tester, measure the voltage between connector (2AB) in test harness AB and chassis ground.

Connector & terminal

(2AB) No. 3 (+) — Chassis ground (−):

Is the voltage 11 V or more?

Replace the seat harness.

Check rear harness, bulkhead wiring harness, instrument panel wiring harness in this order, and replace the faulty harness.

7. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (SHORT CIRCUIT IN IGNITION POWER SUPPLY).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the resistance between occupant detection control module connectors.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB61) No. 7 — (AB61) No. 1 — 12 (except for No. 7):

Is the resistance 1 MΩ or more?

9

8

8. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (SHORT CIRCUIT IN IGNITION POWER SUPPLY).
1.

Disconnect the connector (AB59) of seat harness.

2.

Connect the connector (1AB) in the test harness AB to the connector (AB53).

3.

Using a tester, measure the resistance between terminals in test harness AB connector (2AB).

Connector & terminal

(2AB) No, 3 — (2AB) No. 1 — 6 (except for No. 3):

Is the resistance 1 MΩ or more?

Replace the seat harness.

Check rear harness, bulkhead wiring harness, instrument panel wiring harness in this order, and replace the faulty harness.

9. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (OPEN CIRCUIT IN GROUND).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connectors (AB6, AB17, AB18) from airbag CM.

3.

Connect the connector (1BD) in the test harness BD to the connectors (AB6, AB17, AB18).

4.

Using a tester, measure the resistance in harness between occupant detection control module connector and connector (4BD) in test harness BD.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 2 — (4BD) No. 2:

(AB61) No. 3 — (4BD) No. 7:

Is the resistance less than 10 Ω?

11

10

10. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (OPEN CIRCUIT IN GROUND).
1.

Disconnect the connector (AB59) of seat harness.

2.

Connect the connector (1AB) in the test harness AB to the connector (AB53).

3.

Using a tester, measure the resistance between the test harness AB connector (2AB) and the test harness AG connector (4BD).

Connector & terminal

(2AB) No. 1 — (4BD) No. 2:

(2AB) No. 2 — (4BD) No. 7:

Is the resistance less than 10 Ω?

Replace the seat harness.

Check rear harness, bulkhead wiring harness, instrument panel wiring harness in this order, and replace the faulty harness.

11. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (SHORT CIRCUIT IN GROUND).

Using a tester, measure the resistance between connectors in test harness AG.

Connector & terminal

(4BD) No. 2 — All terminals in test harness BD (except for (4BD) No. 2):

(4BD) No. 7 — All terminals in test harness BD (except for (4BD) No. 7):

Is the resistance 1 MΩ or more?

13

12

12. CHECK HARNESS IN OCCUPANT DETECTION CONTROL MODULE (SHORT CIRCUIT IN GROUND).
1.

Disconnect the connector (AB59) of seat harness.

2.

Using a tester, measure the resistance between connectors in test harness AG.

Connector & terminal

(4BD) No. 2 — All terminals in test harness BD (except for (4BD) No. 2):

(4BD) No. 7 — All terminals in test harness BD (except for (4BD) No. 7):

Is the resistance 1 MΩ or more?

Replace the seat harness.

Check rear harness, bulkhead wiring harness, instrument panel wiring harness in this order, and replace the faulty harness.

13. CHECK FOR POOR CONTACT.

Check for poor contact of connector of occupant detection system.

Is the check result OK?

Replace the occupant detection control module.

Repair or replace the connector. (Replace the harness without repairing the airbag system connector.)

OCCUPANT DETECTION(DIAGNOSTICS) > Data Monitor
OPERATION

- For detailed operation procedures, refer to “Common (Diagnostics)”. COMMON(diag)>Data Monitor

- For details on the data monitor, refer to the list. OCCUPANT DETECTION(DIAGNOSTICS)>Data Monitor>LIST

OCCUPANT DETECTION(DIAGNOSTICS) > Data Monitor
LIST

Items to be displayed | Content | Standard/Unit | Note
Front Passenger Seat Status | Display the status of passenger seat’s occupant. | When status is not confirmed: Unknown When the seat is unoccupied or when child restraint seat is installed: Empty or Child When occupant is adult: Adult or Child | —
Front Passenger Seatbelt Status | Display the status of passenger’s seat buckle switch. | When status is not confirmed or when buckle switch is faulty: Unknown or falut When buckle switch is not engaged: Unbelted When buckle switch is engaged: Belted | —
Front-Left Sensor Load Value | Load value of occupant detection sensor is displayed. | -75.85 — 104.73 kg | —
Front-Right Sensor Load Value | Load value of occupant detection sensor is displayed. | -75.85 — 104.73 kg | —
Rear-Left Sensor Load Value | Load value of occupant detection sensor is displayed. | -75.85 — 104.73 kg | —
Rear-Right Sensor Load Value | Load value of occupant detection sensor is displayed. | -75.85 — 104.73 kg | —
Total Load Value | Total load value of occupant detection sensor is displayed. | -303.40 — 418.94 kg | Set the weight for sensitivity inspection, and check that the load value is nearly equal to it.
Check1 | Information for development | — | Not used.

OCCUPANT DETECTION(DIAGNOSTICS) > Rezero
OPERATION

When any of the following operation has been done, be sure to perform [Rezeroing] of occupant detection system. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

- Replacing occupant detection system

- Removing and disassembling passenger’s seat

- Loosening passenger’s seat bolt

When performing [Rezero], the operation must be completed thoroughly.

1.

Park empty vehicle on a level surface.

2.

Check that all harness and connectors are connected.

3.

Check the following items to adjust the condition of the vehicle.

- Adjust the seat backrest to be fully upright. (For models with power seats, press the power seat button until the backrest comes to a stop.)

- Adjust the lifter position all the way down. (For models with power seat, press the power seat button until the seat does not move any further.) (Model with seat lifter)

- Do not place anything on the top of the seat cushion.

- Sit on the seat cushion to smooth the seat surface.

- Check that the passenger’s seat belt is not inserted into the buckle, not tense or not stuck.

- Check that ambient temperature is in a range from 0 — 40°C (32 — 104°F).

4.

Connect the Subaru Select Monitor.

5.

Turn the ignition switch to OFF, then turn it to ON again.

- This operation is performed to readjust the standard of occupant detection sensor.

- Do not touch the seat until the Rezero is completed. If you have touched the seat even if only once, perform operations from the step 3) again.

6.

On [Start] screen, select [Diagnosis].

7.

On [Vehicle selection] screen, input the target vehicle information and select [OK].

8.

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

9.

On [Select System] screen, select [Occupant Detection].

10.

On [Occupant Detection] screen, select [DTC].

11.

- After replacement of passenger’s seat

  Check that no DTC other than DTC B178C is displayed in current malfunction. When B178B is recorded, this means that [Rezero] for passenger’s seat was not performed at seat factory. In this case, replace the passenger’s seat. When any other DTC is displayed, perform the diagnosis according to the DTC.

- After replacement of the occupant detection control module

  Check that no DTC other than DTC B178B and B178C is displayed in current malfunction. When DTC other than B178B and B178C is displayed, perform the diagnosis according to the DTC.

- When collision detection DTC is recorded

  Check that no DTC other than DTC B1783, B1784, B1785 and B1786 is displayed in current malfunction. Perform the diagnosis according to the DTC.

12.

On [Occupant Detection] screen, select [Work Support].

13.

On [Work Support] screen, select [Rezero].

14.

After [See service manual. And check vehicle condition for successfully completing.] is displayed on the screen, check the vehicle condition and select [Next].

15.

When [Rezero] is performed after replacing the occupant detection control module and passenger’s seat, [Calibration error has occurred. See service manual.] is displayed on the screen. In this case, check the replacement status described in step 11, and select [Next].

16.

[Rezeroing Adjust the passenger seat to the condition shown in service manual.] is displayed on the screen. Slide the passenger’s seat all the way to the front, check that the backrest is adjusted to the most upright position and the lift position of the model with seat lifter is adjusted to the downmost position, and select [Next].

17.

When [Rezeroing Unbelt the passenger seatbelt.] is displayed, make sure the passenger’s seatbelt is disconnected from the buckle and select [Next].

18.

When [Rezeroing Confirm ambient temperature Between 0 and 40°C. (32 and 104°F)] is displayed on the screen, check that ambient temperature at the seat is in a range from 0 — 40°C (32 — 104°F) and select [Next].

19.

When [Rezeroing Empty the passenger seat. Turn ignition OFF, and within 10 seconds, turn ignition ON again.] is displayed on the screen, turn the ignition switch to OFF and then ON again while the passenger’s seat is empty, make sure that airbag OFF indicator illuminates and airbag ON indicator does not illuminate, and then select [Next].

After selecting [Next], [In process... Please wait for a while without touching vehicle.] is displayed. Do not touch or rock the vehicle while the message is displayed.

20.

When the sensor rezero adjustment is complete successfully, [Rezeroing is successfully completed. Press "OK" to END.] is displayed. Select [OK].

- When [Rezeroing is Unsuccessful.] is displayed during sensor rezero adjustment, select [OK] and perform the process according to the displayed error code. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero>LIST

- When [Diagnostic code check. Some troubles occur. See service manual. Press "OK" to END.] is displayed during sensor rezero adjustment, select [OK] and read DTC of [Occupant Detection]. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

  When DTC is displayed, perform the diagnosis according to the DTC, and then perform sensor rezero adjustment. When DTC is not displayed, check the seat and vehicle status and then perform the sensor rezero adjustment again. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

21.

[Next, execute sensor sensitivity check.] is displayed on the screen. Select [OK].

22.

After [See service manual. And check vehicle condition for successfully completing.] is displayed on the screen, check the vehicle condition.

23.

After [Sensitivity check Adjust the passenger seat to the condition shown in service manual.] is displayed on the screen, check that the passenger’s seat does not change from the state confirmed in step 16), and select [Next].

24.

When [Sensitivity check Unbelt the passenger seatbelt.] is displayed, make sure the passenger’s seatbelt is disconnected from the buckle and select [Next].

25.

When [Sensitivity check Confirm ambient temperature Between 0 and 40°C. (32 and 104° F)] is displayed on the screen, check that ambient temperature at the seat is in a range from 0 — 40°C (32 — 104°F) and select [Next].

26.

When [Sensitivity check Empty the passenger seat.] is displayed on the screen, make sure the passenger’s seat is empty and select [Next].

27.

After [According to service manual, prepare the weight / SST whose mass is prescribed for sensitivity check, or measure mass of the weight by high-precision electronic scale] is displayed on the screen, prepare an inspection weight of 30 kg to 40 kg in total, and check that there is no dirt or foreign matter on it.

- If the prepared inspection weight is a weight of which the accuracy has been verified (within ±0.5%), only record the total weight since there is no need of measuring the actual value using a digital scale.

- If the weight value of prepared weight is not verified or the accuracy is unknown, prepare a digital scale and make sure that there is no dirt or foreign matter on it and that the indication is 0 g (kg) when the power is turned on. Then measure and record the total value.

Then select [OK].

If 98399AG000 and 98399AG010 are used together, also check that there is no dirt, foreign matter or damage on them, but there is no need of measuring.

28.

When [Input the total mass value of the prepared weight / SST, or input the measured value of measuring the weight. (Unit: kg)] is displayed on the screen, input the total mass of weight recorded in step 27) and select [Enter].

If 98399AG000 and 98399AG010 are used together, input the total specified weight value: 35.812 kg.

29.

After [Prepare•mass value of the measured weight] is displayed on the screen, check the input value and select [OK].

30.

After [Put the prepared weight on the seat according to service manual.] is displayed on the screen, set the inspection weight on the center of passenger’s seat surface, and select [OK].

After selecting [OK], [In process... Please wait for a while without touching vehicle.] is displayed. Do not touch or rock the vehicle while the message is displayed.

31.

When [Sensitivity check is finished. Read Value : ∗∗∗∗ kg The mass of weight: ∗∗∗∗ kg] is displayed on the screen, select [OK] and turn the ignition switch OFF to exit.

32.

When [Sensitivity check fail. See service manual. Press "OK" to END.] is displayed during sensor sensitive inspection, select [OK] and perform the operation from the beginning. If failure, error code is displayed. Check the error code and fix it. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

OCCUPANT DETECTION(DIAGNOSTICS) > Rezero
LIST

Code | Contents | Causes | Action to take
0020H | Timeout due to unstable load | Occupant detection control module judged the current situation as error because the over-specified load change occurred during rezeroing. | Perform rezeroing again at a stable place where vehicle vibration hardly occurs.
0021H | FL sensor upper limit error | Rezeroing cannot be executed because the load value of FL sensor exceeds the upper limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0022H | FL sensor lower limit error | Rezeroing cannot be executed because the load value of FL sensor exceeds the lower limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0023H | FR sensor upper limit error | Rezeroing cannot be executed because the load value of FR sensor exceeds the upper limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0024H | FR sensor lower limit error | Rezeroing cannot be executed because the load value of FR sensor exceeds the lower limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0025H | RL sensor upper limit error | Rezeroing cannot be executed because the load value of RL sensor exceeds the upper limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0026H | RL sensor lower limit error | Rezeroing cannot be executed because the load value of RL sensor exceeds the lower limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0027H | RR sensor upper limit error | Rezeroing cannot be executed because the load value of RR sensor exceeds the upper limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0028H | RR sensor lower limit error | Rezeroing cannot be executed because the load value of RR sensor exceeds the lower limit of rezero adjustment range. | Check that the seat is in proper position and fixed securely, and perform rezeroing again. If the same code appears again, replace the seat assembly. SEATS>Front Seat
0029H | Sensor malfunction | Rezeroing cannot be performed due to sensor malfunction during rezeroing. | Read the DTC of [Occupant Detection] OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC), and perform the diagnosis for the displayed DTCs. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST
0030H | Memory access error | Rezeroing cannot be performed due to data flash malfunction during rezeroing. | Read the DTC of [Occupant Detection] OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC), and perform the diagnosis for the displayed DTCs. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

OCCUPANT DETECTION(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. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Trouble Code (DTC)
LIST

Code | Description & trouble part | Reference
B1650 | OCCUPANT DETECTION SYSTEM MALFUNCTION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1650 OCCUPANT DETECTION SYSTEM MALFUNCTION
B1655 | FRONT BUCKLE SWITCH RH FAILURE | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1655 FRONT BUCKLE SWITCH RH FAILURE
B1771 | BUCKLE SWITCH | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1771 BUCKLE SWITCH
B177F | FRONT LEFT OCCUPANT DETECTION SENSOR | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B177F FRONT LEFT OCCUPANT DETECTION SENSOR
B1780 | FRONT RIGHT OCCUPANT DETECTION SENSOR | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1780 FRONT RIGHT OCCUPANT DETECTION SENSOR
B1781 | REAR LEFT OCCUPANT DETECTION SENSOR | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1781 REAR LEFT OCCUPANT DETECTION SENSOR
B1782 | REAR RIGHT OCCUPANT DETECTION SENSOR | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1782 REAR RIGHT OCCUPANT DETECTION SENSOR
B1783 | FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1783 FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION
B1784 | FRONT RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1784 FRONT RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION
B1785 | REAR LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1785 REAR LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION
B1786 | REAR RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1786 REAR RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION
B1787 | VEHICLE SPEED INFORMATION | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1787 VEHICLE SPEED INFORMATION
B1788 | OCCUPANT DETECTION SENSOR POWER SUPPLY | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1788 OCCUPANT DETECTION SENSOR POWER SUPPLY
B1789 | +B POWER SUPPLY | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1789 +B POWER SUPPLY
B178A | ECU INTERNAL CIRCUIT FAULT | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B178A ECU INTERNAL CIRCUIT FAULT
B178B | SEAT FACTORY CALIBRATION UNCOMPLETED | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B178B SEAT FACTORY CALIBRATION UNCOMPLETED
B178C | VEHICLE FACTORY CALIBRATION UNCOMPLETED | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B178C VEHICLE FACTORY CALIBRATION UNCOMPLETED
B1795 | OCCUPANT DETECTION MODULE INTERNAL CIRCUIT | OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1795 OCCUPANT DETECTION MODULE INTERNAL CIRCUIT

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1650 OCCUPANT DETECTION SYSTEM MALFUNCTION

For DTC B1650, refer to “AIRBAG SYSTEM”. AIRBAG(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1650 OCCUPANT DETECTION SYSTEM MALFUNCTION

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1655 FRONT BUCKLE SWITCH RH FAILURE

For DTC B1655, refer to “AIRBAG SYSTEM”. AIRBAG(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1655 FRONT BUCKLE SWITCH RH FAILURE

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1771 BUCKLE SWITCH

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

- Open circuit, ground short circuit or short circuit to power supply in buckle switch harness

- Buckle switch malfunction (Communication circuit failure)

- Occupant detection control module buckle communication circuit malfunction

Trouble symptom:

Communication fails between occupant detection control module and buckle switch.

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. AIRBAG(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC B177F, B1780, B1781, B1782, B1788, B178A or B1795 displayed? (Current malfunction)

Perform the diagnosis for the displayed DTC B177F, B1780, B1781, B1782, B1788, B178A or B1795.

2

2. CHECK DTC.

Read the DTC of [Airbag] using the Subaru Select Monitor. AIRBAG(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1655 displayed? (Current malfunction)

3

Replace the occupant detection control module.

3. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB61) from occupant detection control module.

3.

Disconnect the connector (AB60) from the passenger’s buckle switch.

4.

Connect the connector (2D) in the test harness D to the connector (AB60).

5.

Using a tester, measure the resistance between occupant detection control module connector and connector (3D) in test harness D.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 5 — (3D) No. 5:

(AB61) No. 9 — (3D) No. 6:

Is the resistance less than 10 Ω?

4

Replace the seat harness.

4. CHECK SEAT HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB61) No. 5 — All terminals other than (AB61) No. 5:

(AB61) No. 9 — All terminals other than (AB61) No. 9:

(AB61) No. 5 — Chassis ground:

(AB61) No. 9 — Chassis ground:

Is the resistance 1 MΩ or more?

5

Replace the seat harness.

5. CHECK SEAT HARNESS (BATTERY SHORT).
1.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 5 (+) — Chassis ground (−):

(AB61) No. 9 (+) — Chassis ground (−):

Is the voltage less than 1 V?

6

Replace the seat harness.

6. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Check for poor contact in occupant detection control module connector and passenger’s buckle switch connector.

Is the check result OK?

7

Repair or replace the poor contact part.

7. CHECK PASSENGER’S SEAT BUCKLE SWITCH.
1.

Disconnect the test harness D and test harness BC.

2.

Connect the occupant detection control module connector.

3.

Connect the test harness AE and test harness connector Y to buckle switch connector (AB60).

4.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

Does the airbag warning light illuminate for 6 seconds and go off?

Replace the buckle switch. SEAT BELT SYSTEM>Front Seat Belt>REMOVAL > BELT ASSEMBLY FRONT OUT

Replace the occupant detection control module.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B177F FRONT LEFT OCCUPANT DETECTION SENSOR

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Occupant detection sensor malfunction

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC B1788, B178A or B1795 displayed? (Current malfunction)

Perform the diagnosis for the displayed DTC B1788, B178A or B1795. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB69) from occupant detection control module.

3.

Disconnect connector (AB70) from the load sensor FL.

4.

Using a tester, measure the resistance between occupant detection control module connector and load sensor FL connector.

Connect the terminal in test harness BC to connector (AB69) and connector (AB70) terminals, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 1 — (AB70) No. 3:

(AB69) No. 7 — (AB70) No. 2:

(AB69) No. 11 — (AB70) No. 1:

Is the resistance less than 10 Ω?

3

Replace the seat harness.

3. CHECK SEAT HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 1 — All terminals other than (AB69) No. 1:

(AB69) No. 7 — All terminals other than (AB69) No. 7:

(AB69) No. 11 — All terminals other than (AB69) No. 11:

(AB69) No. 1 — Chassis ground:

(AB69) No. 7 — Chassis ground:

(AB69) No. 11 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Replace the seat harness.

4. CHECK SEAT HARNESS (BATTERY SHORT).
1.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB69) No. 1 (+) — Chassis ground (−):

(AB69) No. 7 (+) — Chassis ground (−):

(AB69) No. 11 (+) — Chassis ground (−):

Is the voltage less than 1 V?

5

Replace the seat harness.

5. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Check for poor contact in occupant detection control module connector and load sensor connector.

3.

Disconnect the test harness BC, and connect all the connectors.

4.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B177F displayed? (Current malfunction)

Replace the cushion frame assembly. SEATS>Front Seat

Finish the diagnosis.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1780 FRONT RIGHT OCCUPANT DETECTION SENSOR

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Occupant detection sensor malfunction

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC B1788, B178A or B1795 displayed? (Current malfunction)

Perform the diagnosis for the displayed DTC B1788, B178A or B1795. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB69) from occupant detection control module.

3.

Disconnect connector (AB72) from the load sensor FR.

4.

Using a tester, measure the resistance between occupant detection control module connector and load sensor FR connector.

Connect the terminal in test harness BC to connector (AB69) and connector (AB72) terminals, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 2 — (AB72) No. 3:

(AB69) No. 8 — (AB72) No. 2:

(AB69) No. 12 — (AB72) No. 1:

Is the resistance less than 10 Ω?

3

Replace the seat harness.

3. CHECK SEAT HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 2 — All terminals other than (AB69) No. 2:

(AB69) No. 8 — All terminals other than (AB69) No. 8:

(AB69) No. 12 — All terminals other than (AB69) No. 12:

(AB69) No. 2 — Chassis ground:

(AB69) No. 8 — Chassis ground:

(AB69) No. 12 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Replace the seat harness.

4. CHECK SEAT HARNESS (BATTERY SHORT).
1.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB69) No. 2 (+) — Chassis ground (−):

(AB69) No. 8 (+) — Chassis ground (−):

(AB69) No. 12 (+) — Chassis ground (−):

Is the voltage less than 1 V?

5

Replace the seat harness.

5. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Check for poor contact in occupant detection control module connector and load sensor connector.

3.

Disconnect the test harness BC, and connect all the connectors.

4.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1780 displayed? (Current malfunction)

Replace the cushion frame assembly. SEATS>Front Seat

Finish the diagnosis.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1781 REAR LEFT OCCUPANT DETECTION SENSOR

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Occupant detection sensor malfunction

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC B1788, B178A or B1795 displayed? (Current malfunction)

Perform the diagnosis for the displayed DTC B1788, B178A or B1795. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB69) from occupant detection control module.

3.

Disconnect connector (AB71) from the load sensor RL.

4.

Using a tester, measure the resistance between occupant detection control module connector and load sensor RL connector.

Connect the terminal in test harness BC to connector (AB69) and connector (AB71) terminals, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 3 — (AB71) No. 3:

(AB69) No. 9 — (AB71) No. 2:

(AB69) No. 5 — (AB71) No. 1:

Is the resistance less than 10 Ω?

3

Replace the seat harness.

3. CHECK SEAT HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 3 — All terminals other than (AB69) No. 3:

(AB69) No. 9 — All terminals other than (AB69) No. 9:

(AB69) No. 5 — All terminals other than (AB69) No. 5:

(AB69) No. 3 — Chassis ground:

(AB69) No. 9 — Chassis ground:

(AB69) No. 5 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Replace the seat harness.

4. CHECK SEAT HARNESS (BATTERY SHORT).
1.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 3 (+) — Chassis ground (−):

(AB69) No. 9 (+) — Chassis ground (−):

(AB69) No. 5 (+) — Chassis ground (−):

Is the voltage less than 1 V?

5

Replace the seat harness.

5. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Check for poor contact in occupant detection control module connector and load sensor connector.

3.

Disconnect the test harness BC, and connect all the connectors.

4.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1781 displayed? (Current malfunction)

Replace the cushion frame assembly. SEATS>Front Seat

Finish the diagnosis.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1782 REAR RIGHT OCCUPANT DETECTION SENSOR

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Occupant detection sensor malfunction

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC B1788, B178A or B1795 displayed? (Current malfunction)

Perform the diagnosis for the displayed DTC B1788, B178A or B1795. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB69) from occupant detection control module.

3.

Disconnect connector (AB73) from the load sensor RR.

4.

Using a tester, measure the resistance between occupant detection control module connector and load sensor RR connector.

Connect the terminal in test harness BC to connector (AB69) and connector (AB73) terminals, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 4 — (AB73) No. 3:

(AB69) No. 10 — (AB73) No. 2:

(AB69) No. 6 — (AB73) No. 1:

Is the resistance less than 10 Ω?

3

Replace the seat harness.

3. CHECK SEAT HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB69) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB69) No. 4 — All terminals other than (AB69) No. 4:

(AB69) No. 10 — All terminals other than (AB69) No. 10:

(AB69) No. 6 — All terminals other than (AB69) No. 6:

(AB69) No. 4 — Chassis ground:

(AB69) No. 10 — Chassis ground:

(AB69) No. 6 — Chassis ground:

Is the resistance 1 MΩ or more?

4

Replace the seat harness.

4. CHECK SEAT HARNESS (BATTERY SHORT).
1.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

2.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB69) and connector (AB73) terminals, and apply the tester to test harness BC.

Connector & terminal

(AB69) No. 4 (+) — Chassis ground (−):

(AB69) No. 10 (+) — Chassis ground (−):

(AB69) No. 6 (+) — Chassis ground (−):

Is the voltage less than 1 V?

5

Replace the seat harness.

5. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Check for poor contact in occupant detection control module connector and load sensor connector.

3.

Disconnect the test harness BC, and connect all the connectors.

4.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1782 displayed? (Current malfunction)

Replace the cushion frame assembly. SEATS>Front Seat

Finish the diagnosis.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1783 FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Load sensor detects a collision.

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. CHECK AIRBAG SYSTEM OPERATION.

Check the operation status of the airbag system.

Is there any airbag system operated?

Replace the seat assembly. SEATS>Front Seat

Perform inspection referring to inspection part after collision. AIRBAG SYSTEM>Inspection Locations after a Collision

2

2. PERFORM [Rezero].

Perform [Rezero]. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

Is [Rezero] completed?

3

Perform operation according to an error code displayed when [Rezero] fails. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero>LIST

3. CHECK OCCUPANT DETECTION CONTROL MODULE.
1.

Using the Subaru Select Monitor, perform the clear memory of [Occupant Detection]. COMMON(diag)>Clear memory

2.

Execute the inspection mode. OCCUPANT DETECTION(DIAGNOSTICS)>Inspection Mode

3.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1783, B1784, B1785 or B1786 displayed? (Current malfunction)

Replace the occupant detection control module.

Currently, it is normal.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1784 FRONT RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION

For details on DTC B1784, refer to DTC B1783. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1783 FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1785 REAR LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION

For details on DTC B1785, refer to DTC B1783. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1783 FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1786 REAR RIGHT OCCUPANT DETECTION SENSOR COLLISION DETECTION

For details on DTC B1786, refer to DTC B1783. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1783 FRONT LEFT OCCUPANT DETECTION SENSOR COLLISION DETECTION

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1787 VEHICLE SPEED INFORMATION

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

- VDC malfunction

- CAN communication failure

- Occupant detection control module malfunction

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. CHECK DTC.
1.

Turn the ignition switch to OFF.

2.

Turn the ignition switch to ON.

3.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B1787 displayed? (Current malfunction)

2

- Even if DTC is displayed, 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 DTC.

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

Is DTC U∗∗∗∗ displayed? (Current malfunction)

Perform the diagnosis for LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure>PROCEDURE

3

3. CHECK VDC.

Read the DTC of [Brake Control] using the Subaru Select Monitor. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC related to vehicle speed displayed? (Current malfunction)

Perform the diagnosis for the displayed DTCs. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

Replace the occupant detection control module.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1788 OCCUPANT DETECTION SENSOR POWER SUPPLY

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

Occupant detection control module malfunction

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. CHECK DTC.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is any of DTC 177F, B1780, B1781 or B1782 displayed? (Current malfunction)

Replace the cushion frame assembly. SEATS>Front Seat

Replace the occupant detection control module.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1789 +B POWER SUPPLY

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

- Poor contact in harness between occupant detection CM and battery

- Battery malfunction

- Occupant detection control module malfunction

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Wiring diagram:

Occupant detection system WIRING SYSTEM>Occupant Detection System>WIRING DIAGRAM

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

Before starting work, prepare two sets of TEST HARNESS BC (98299FL030).

1. CHECK BATTERY.

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery>INSPECTION

Is the check result OK?

2

Charge or replace the battery.

2. CHECK FUSE.

Check the fuse of occupant detection control module.

Is the fuse OK?

3

Replace the fuse. If the replaced fuse blows out easily, repair or replace the short circuit in the harness between battery and occupant detection control module.

3. CHECK OCCUPANT DETECTION CONTROL MODULE CONNECTOR.
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Confirm that the connector of the occupant detection control module (AB61) is securely connected.

Is the connector of the occupant detection control module securely connected?

4

Reconnect the connector of the occupant detection control module.

4. CHECK HARNESS (OPEN CIRCUIT BETWEEN BATTERY AND OCCUPANT DETECTION CONTROL MODULE).
1.

Disconnect the connector (AB61) of occupant detection control module.

2.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

3.

Using a tester, measure the voltage between occupant detection control module connector and chassis ground.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 1 (+) — Chassis ground (−):

Is the voltage 10 V or more?

8

5

5. CHECK HARNESS (OPEN CIRCUIT BETWEEN BATTERY AND REAR HARNESS).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Disconnect the connector (AB59) of seat harness.

3.

Connect the connector (1AB) in the test harness AB to the connector (AB53).

4.

Install the ground terminal to the battery sensor and turn the ignition switch to ON.REPAIR CONTENTS>NOTE > BATTERY

5.

Using a tester, measure the voltage between connector (2AB) in test harness AB and chassis ground.

Connector & terminal

(2AB) No. 6 (+) — Chassis ground (−):

Is the voltage 10 V or more?

6

Check rear harness, instrument panel wiring harness, bulkhead wiring harness in this order, and replace the faulty harness.

6. CHECK SEAT HARNESS (OPEN CIRCUIT).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Connect the connector (1BB) in the test harness BB to the connector (AB59).

3.

Using a tester, measure the resistance between occupant detection control module connector and connector (2BB) in test harness BB.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 1 — (2BB) No. 6:

Is the resistance less than 10 Ω?

7

Replace the seat harness.

7. CHECK SEAT HARNESS (SHORT).

Using a tester, measure the resistance between occupant detection control module connector and chassis ground, and between occupant detection control module connector terminals.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC. Two sets of test harness BC are required.

Connector & terminal

(AB61) No. 1 — Chassis ground:

(AB61) No. 1 — All terminals other than (AB61) No. 1:

Is the resistance 1 MΩ or more?

8

Replace the seat harness.

8. CHECK HARNESS (OPEN CIRCUIT BETWEEN OCCUPANT DETECTION CONTROL MODULE AND GROUND).
1.

Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor.REPAIR CONTENTS>NOTE > BATTERY

2.

Connect all the connectors other than (AB61) of occupant detection control module.

3.

Using a tester, measure the resistance between occupant detection control module connector (AB61) and chassis ground.

Connect the terminal in test harness BC to connector (AB61) terminal, and apply the tester to test harness BC.

Connector & terminal

(AB61) No. 3 — Chassis ground:

Is the resistance less than 10 Ω?

11

9

9. CHECK HARNESS (OPEN CIRCUIT BETWEEN REAR HARNESS AND GROUND).
1.

Disconnect the connector (AB59) of seat harness.

2.

Connect the connector (1AB) in the test harness AB to the connector (AB53).

3.

Using a tester, measure the resistance between connector (2AB) in test harness AB and chassis ground.

Connector & terminal

(2AB) No. 2 — Chassis ground:

Is the resistance less than 10 Ω?

Replace the seat harness.

10

10. CHECK HARNESS (OPEN CIRCUIT BETWEEN AIRBAG CM AND GROUND).
1.

Disconnect the connectors (AB6, AB17, AB18) from airbag control module.

2.

Connect the connector (1BD) in the test harness BD to the connectors (AB6, AB17, AB18).

3.

Using a tester, measure the resistance between connector (2BD) in test harness BD and chassis ground.

Connector & terminal

(2BD) No. 16 — Chassis ground:

(2BD) No. 17 — Chassis ground:

Is the resistance less than 10 Ω?

11

Check for poor contact in grounding point. If faulty, repair it.

11. CHECK POOR CONTACT OF CONNECTORS.

Check for poor contact in the connector of the occupant detection control module.

Is there poor contact?

Repair or replace the connector. (Replace the harness without repairing the airbag system connector.)

Replace the occupant detection control module.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B178A ECU INTERNAL CIRCUIT FAULT

For details on DTC B178A, refer to DTC B1788. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1788 OCCUPANT DETECTION SENSOR POWER SUPPLY

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B178B SEAT FACTORY CALIBRATION UNCOMPLETED

Diagnosis start condition:

When the ignition voltage is 10 V — 16 V

DTC detecting condition:

Sensor rezero adjustment was not performed at seat factory.

This DTC is detected only when replacing the occupant detection control module. When this DTC is detected at replacement of passenger’s seat, this means that [Rezeroing] for the passenger’s seat assembly was not performed at seat factory before shipping. In this case, replace the passenger’s seat assembly.

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. CHECK OPERATION.

Confirm which one was replaced, occupant detection control module or passenger’s seat.

Is it the occupant detection control module that was replaced?

Perform [Rezeroing]. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

Replace the passenger’s seat assembly.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B178C VEHICLE FACTORY CALIBRATION UNCOMPLETED

Diagnosis start condition:

When the ignition voltage is 10 — 16 V.

DTC detecting condition:

- [Rezeroing] for the occupant detection system was not performed at vehicle factory.

- [Rezeroing] was not performed after replacing the occupant detection control module.

- [Rezeroing] was not performed after replacing the passenger’s seat assembly.

Trouble symptom:

Occupant judgment of occupant detection control module stops.

Before performing diagnosis, refer to “CAUTION” in “General Description”. OCCUPANT DETECTION(DIAGNOSTICS)>General Description>CAUTION

1. PERFORM [Rezeroing].
1.

Perform [Rezeroing]. OCCUPANT DETECTION(DIAGNOSTICS)>Rezero

2.

Using the Subaru Select Monitor, perform the clear memory of [Occupant Detection]. COMMON(diag)>Clear memory

3.

Execute the inspection mode. OCCUPANT DETECTION(DIAGNOSTICS)>Inspection Mode

4.

Read the DTC of [Occupant Detection] using the Subaru Select Monitor. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC B178C displayed? (Current malfunction)

Replace the occupant detection control module.

[Rezeroing] was not performed.

OCCUPANT DETECTION(DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC B1795 OCCUPANT DETECTION MODULE INTERNAL CIRCUIT

For details on DTC B1795, refer to DTC B1788. OCCUPANT DETECTION(DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC B1788 OCCUPANT DETECTION SENSOR POWER SUPPLY