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COMMUNICATION SYSTEM > General Description
COMPONENT

(1) | Horn switch (driver’s airbag module) | (4) | Horn ASSY Hi | Tightening torque: N·m (kgf-m, ft-lb)
(2) | Steering roll connector | (5) | Horn ASSY Lo | T: | 18 (1.8, 13.3)
(3) | Horn relay |  |  |  |

COMMUNICATION SYSTEM > General Description
CAUTION

- When performing service operation, refer to “Repair Contents” in “General Description”. REPAIR CONTENTS>Repair Contents

- Before performing vehicle maintenance, turn the ignition switch to OFF and disconnect the ground terminal from the battery sensor. REPAIR CONTENTS>NOTE > BATTERY

- When replacing the audio and MFD parts provided with memory functions, record the memory contents before disconnecting the ground terminal from the battery sensor.

- Be careful of the following items. Failing to do so may cause the airbag system malfunction.

  - Yellow connectors and harnesses with yellow tapes around them are the connectors and harnesses for the airbag system. When using a tester on these circuits, follow the cautions of “AIRBAG SYSTEM”.

  - Be careful not to damage the airbag system wiring harness when servicing the electrical parts around the steering column. AIRBAG SYSTEM>General Description>CAUTION

- If the hydraulic unit assembly VDC, bracket COMPL hydraulic unit VDC, steering wheel and the sensor assembly VDC steering (steering roll connector) are removed, installed or replaced, perform “VSC(VDC) Centering Mode” of the VDC. VEHICLE DYNAMICS CONTROL (VDC)>VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)>ADJUSTMENT

COMMUNICATION SYSTEM > General Description
PREPARATION TOOL
1. GENERAL TOOL

TOOL NAME | REMARKS
Circuit tester | Used for measuring resistance, voltage and current.

COMMUNICATION SYSTEM > Relay and Fuse
LOCATION

Main fuse box (M/B) | Horn relay | (A)
Fuse 7.5 A (horn ASSY Hi) | (B)
Fuse 7.5 A (horn ASSY Lo) | (C)

For other related fuses, refer to the wiring diagram. WIRING SYSTEM>Power Supply Circuit

COMMUNICATION SYSTEM > Relay and Fuse
INSPECTION
1. CHECK FUSE
1.

Remove the fuse and inspect visually.

2.

If the fuse is blown out, replace the fuse.

2. CHECK RELAY
1.

Check the resistance between relay terminals.

Terminal No. | Inspection conditions | Standard | Circuit
1 — 3 | Always | 1 MΩ or more |
1 — 3 | Apply battery voltage between terminals 2 and 4. | Less than 1 Ω

2.

Replace the relay if the inspection result is not within the standard value.

COMMUNICATION SYSTEM > Horn System
WIRING DIAGRAM

Refer to “Horn System” in the wiring diagram. WIRING SYSTEM>Horn System>WIRING DIAGRAM

COMMUNICATION SYSTEM > Horn System
INSPECTION

Symptoms | Inspection steps
Horn does not sound | 1. Check the fuse.
2. Check the horn relay.
3. Check the steering roll connector.
4. Check the horn switch.
5. Check the horn assembly.
6. Check the harness.

COMMUNICATION SYSTEM > Horn System
NOTE

For procedure of each component in the horn system, refer to the respective section.

- Horn assembly: COMMUNICATION SYSTEM>Horn

- Horn switch: COMMUNICATION SYSTEM>Horn Switch

COMMUNICATION SYSTEM > Horn
REMOVAL
1. HORN ASSEMBLY HI
1.

Disconnect the ground terminal from battery sensor. REPAIR CONTENTS>NOTE > BATTERY

2.

Remove the air intake duct (rear). INTAKE (INDUCTION)(H4DO)>Air Intake Duct>REMOVAL

3.

Remove the bracket grille front.

(1)

Apply the protective tapes on the bracket grille front and the grille assembly front LWR.

(2)

Remove the clips, and remove the bracket grille front.

4.

Remove the horn assembly Hi.

(1)

Disconnect the connector.

(2)

Remove the bolt, and remove the horn assembly Hi.

2. HORN ASSEMBLY LO

When removing the horn, do not remove the bumper face front. Bracket connection portion of the bumper face may become damaged.

1.

Disconnect the ground terminal from battery sensor. REPAIR CONTENTS>NOTE > BATTERY

2.

Lift up the vehicle.

3.

Remove the under cover front. EXTERIOR/INTERIOR TRIM>Front Under Cover>REMOVAL

4.

Remove the screw and clips, and turn over the mud guard front on the right side.

5.

Remove the horn assembly Lo.

(1)

Disconnect the connector.

(2)

Remove the bolt, and remove the horn assembly Lo.

COMMUNICATION SYSTEM > Horn
INSTALLATION

Install the mud guard front so that the front end of the mud guard (b), except for the clip fixing point, comes inside the bumper face (a).

1.

Install the horn assembly.

Tightening torque:

18 N·m (1.8 kgf-m, 13.3 ft-lb)

2.

Install the mud guard front. (Lo side)

3.

Install the under cover front. (Lo side)

Tightening torque:

18 N·m (1.8 kgf-m, 13.3 ft-lb)

4.

Lower the vehicle. (Lo side)

5.

Install the bracket grille front. (Hi side)

6.

Install the air intake duct (rear). (Hi side)

7.

Connect the ground terminal to battery sensor. REPAIR CONTENTS>NOTE > BATTERY

COMMUNICATION SYSTEM > Horn
INSPECTION
1.

Remove the horn assembly. COMMUNICATION SYSTEM>Horn>REMOVAL

2.

Check the horn sounds when applying the battery voltage to the horn assembly.

- Horn assembly Lo side

- Horn assembly Hi side

  Terminal No. | Inspection conditions | Specification
  1 (+) — Horn case (−) | Connect battery to the terminals | Sounds

3.

If it does not operate normally, replace the horn assembly.

COMMUNICATION SYSTEM > Horn Switch
NOTE

Horn switch is a unit with the driver’s airbag module. For operation procedures, refer to “Driver’s Airbag Module” in “AIRBAG SYSTEM”. AIRBAG SYSTEM>Driver’s Airbag Module

COMMUNICATION SYSTEM > Horn Switch
INSPECTION
1. CHECK HORN SWITCH

Before handling the airbag system components, refer to “CAUTION” of “General Description” in “AIRBAG SYSTEM”. AIRBAG SYSTEM>General Description>CAUTION

1. CHECK HORN SWITCH TERMINAL.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ground terminal from the battery sensor, and wait for at least 60 seconds before starting work. REPAIR CONTENTS>NOTE > BATTERY

3.

Remove the driver’s airbag module. AIRBAG SYSTEM>Driver’s Airbag Module>REMOVAL

4.

Check that the connection of the horn switch harness connector is correct.

5.

Measure the resistance between connectors.

Preparation tool:

Circuit tester

(a) | Ground terminal
(b) | Horn switch terminal

Terminal No. | Standard
Horn switch terminal — ground terminal | Less than 1 Ω

Is the measured value within the standard value?

2

It is possible that there is an open circuit between horn switch terminal and ground terminal. Replace the satellite switch assembly.

2. CHECK DRIVER’S AIRBAG MODULE.

Measure the resistance between horn plate and snap pin hook.

Preparation tool:

Circuit tester

Terminal No. | Standard
Horn plate — Snap pin hook | 1 MΩ or more

Is the measured resistance 1 MΩ or more?

3

Replace the driver’s airbag module.

3. CHECK DRIVER’S AIRBAG MODULE.

Measure the resistance between horn plate and snap pin hook with the snap pin hook pressed-in firmly.

Preparation tool:

Circuit tester

Terminal No. | Standard
Horn plate — Snap pin hook | Less than 1 Ω

Is the measured resistance less than 1 Ω?

Driver’s airbag module is normal.

Replace the driver’s airbag module.

2. CHECK STEERING ROLL CONNECTOR

- Before handling the airbag system components, refer to “CAUTION” of “General Description” in “AIRBAG SYSTEM”. AIRBAG SYSTEM>General Description>CAUTION

- If the steering wheel and steering angle sensor (steering roll connector) are removed, be sure to perform the following operations.

  - Align the center position of the steering roll connector.

  - Perform the neutral position setting of the steering angle sensor.

1. CHECK STEERING ROLL CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ground terminal from the battery sensor, and wait for at least 60 seconds before starting work. REPAIR CONTENTS>NOTE > BATTERY

3.

Measure the resistance between connectors.

Preparation tool:

Circuit tester

Terminal No. | Inspection conditions | Standard
A1 — C9 | Always | Less than 1 Ω

Is the measured value within the standard value?

The steering roll connector is normal.

Replace the steering roll connector.

3. CHECK THE VEHICLE HARNESS

- Before handling the airbag system components, refer to “CAUTION” of “General Description” in “AIRBAG SYSTEM”. AIRBAG SYSTEM>General Description>CAUTION

- If the steering wheel and steering angle sensor (steering roll connector) are removed, be sure to perform the following operations.

  - Align the center position of the steering roll connector.

  - Perform the neutral position setting of the steering angle sensor.

1. CHECK THE VEHICLE HARNESS.
1.

Turn the ignition switch to OFF.

2.

Disconnect the ground terminal from the battery sensor, and wait for at least 60 seconds before starting work. REPAIR CONTENTS>NOTE > BATTERY

3.

Measure the resistance between connector — 12 V battery+ terminal side harness.

Preparation tool:

Circuit tester

Terminal No. | Standard
C-9 — 12 V battery+ terminal side harness | Less than 1 Ω

Is the measured value less than 1 Ω?

Vehicle harness is normal.

Repair the open circuit of vehicle harness.