Steering System (Circuit Diagnosis)
- CHECK POWER CIRCUIT
- Turn ignition switch OFF.
- Remove the heated steering wheel switch. Refer to Removal and Installation .
- Turn ignition switch ON.
- Check voltage between heated steering wheel switch harness connector terminals.
Connector
Terminal
Voltage (Approx.)
+
-
M48
1
2
Battery voltage
Is the inspection result normal?
YES
GO TO 2.
NO
GO TO 7.
- CHECK GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect heated steering wheel switch connector.
- Check continuity between heated steering wheel switch harness connector terminal and ground.
Connector
Terminal
Ground
Continuity
M48
6
Yes
Is the inspection result normal?
YES
GO TO 3.
NO
Repair harness or connector.
- CHECK HARNESS BETWEEN HEATED STEERING RELAY AND HEATED STEERING WHEEL SWITCH
- Disconnect heated steering relay connector.
- Check continuity between heated steering relay harness connector terminal and heated steering wheel switch harness connector terminal.
Heated steering relay
Heated steering wheel switch
Continuity
Connector
Terminal
Connector
Terminal
M90
5
M48
5
Yes
- Check continuity between heated steering relay harness connector terminal and ground.
Connector
Terminal
Ground
Continuity
M90
5
No
Is the inspection result normal?
YES
GO TO 4.
NO
Repair harness or connector.
- CHECK HEATED STEERING RELAY
Check heated steering relay. Refer to Component Inspection (Heated Steering Relay) .
Is the inspection result normal?
YES
GO TO 5.
NO
Replace heated steering relay.
- CHECK BATTERY POWER
Check the following:
- Battery
- Harness for open or short between battery and 10 A fuse (No. 74)
- 10 A fuse (No. 74)
- Harness for open or short between 10 A fuse (No. 74) and heated steering wheel relay
Is the inspection result normal?
YES
GO TO 6.
NO
Repair harness or connector.
- CHECK HARNESS BETWEEN A/C AUTO AMP. AND HEATED STEERING WHEEL RELAY
- Check continuity between A/C auto amp. harness connector terminal and heated steering wheel relay harness connector terminal.
A/C auto amp.
Heated steering wheel relay
Continuity
Connector
Terminal
Connector
Terminal
M50
20
M90
2
Yes
- Check continuity between A/C auto amp. harness connector terminal and ground.
A/C auto amp.
Ground
Continuity
Connector
Terminal
M50
20
No
Is the inspection result normal?
YES
GO TO 9.
NO
Repair harness or connector.
- Check continuity between A/C auto amp. harness connector terminal and heated steering wheel relay harness connector terminal.
- CHECK HARNESS BETWEEN A/C AUTO AMP. AND HEATED STEERING WHEEL SWITCH
- Check continuity between A/C auto amp. harness connector terminal and heated steering wheel switch harness connector terminal.
A/C auto amp.
Heated steering wheel switch
Continuity
Connector
Terminal
Connector
Terminal
M50
8
M48
1
Yes
- Check continuity between A/C auto amp. harness connector terminal and ground.
A/C auto amp.
Ground
Continuity
Connector
Terminal
M50
8
No
Is the inspection result normal?
YES
GO TO 8.
NO
Repair or replace harness or connector.
- Check continuity between A/C auto amp. harness connector terminal and heated steering wheel switch harness connector terminal.
- CHECK GROUND CIRCUIT
- Disconnect heated steering wheel switch.
- Check continuity between heated steering wheel switch harness connector terminal and ground.
Connector
Terminal
Ground
Continuity
M48
2
Yes
Is the inspection result normal?
YES
GO TO 9.
NO
Repair or replace harness or connector.
- CHECK HEATED STEERING WHEEL SWITCH
Check heated steering wheel switch. Refer to Component Inspection (Heated Steering Wheel Switch) .
Is the inspection result normal?
YES
Replace A/C auto amp. Refer to Removal and Installation
NO
Replace heated steering wheel switch. Refer to Removal and Installation .