Steering Wheel does not Heat Up When Heated Steering Wheel Switch is Pressed

STEERING COLUMN: HEATED STEERING WHEEL SYSTEM: Steering Wheel does not Heat Up When Heated Steering Wheel Switch is Pressed
- Steering Wheel does not Heat Up When Heated Steering Wheel Switch is Pressed

DESCRIPTION





HINT
* The heated steering wheel switch is built into the outer mirror switch.
* As the outer mirror switch cannot be disassembled, replace the outer mirror switch when there is a malfunction in the heated steering wheel switch.
* The heated steering wheel unit is built into the steering wheel.
* As the steering wheel cannot be disassembled, replace the steering wheel when there is a malfunction in the heated steering wheel unit.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OUTER MIRROR SWITCH (LED OPERATION)





(a) Check the illumination condition of the LED.

Result:





B -- INSPECT STEERING WHEEL ASSEMBLY (HEATER-THERMOSTAT)
A -- Continue to next step.

2. INSPECT STEERING WHEEL ASSEMBLY (THERMISTOR)





(a) Disconnect the steering wheel controller connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:





NG -- REPLACE STEERING WHEEL ASSEMBLY Removal
OK -- Continue to next step.

3. INSPECT STEERING WHEEL ASSEMBLY (HEATER-THERMOSTAT)





(a) Disconnect the steering wheel controller connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:





NG -- REPLACE STEERING WHEEL ASSEMBLY Removal
OK -- Continue to next step.

4. INSPECT FUSE (D-IG1-4)

(a) Remove the D-IG1-4 fuse from the main body ECU.

(b) Measure the resistance of the fuse.

Standard resistance:





NG -- REPLACE FUSE
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (OUTER MIRROR SWITCH - SPIRAL CABLE)





(a) Disconnect the L6 outer mirror switch connector.

(b) Disconnect the L23 spiral cable connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard resistance:





(d) Measure the voltage according to the value(s) in the table below.

Standard voltage:





NG -- REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. INSPECT SPIRAL CABLE SUB-ASSEMBLY

NOTICE:
If there are any defects as mentioned below, replace the spiral cable with a new one:

Scratches, cracks, dents or chips on the connector or the spiral cable.





(a) Disconnect the L23 spiral cable connector.

(b) Disconnect the heated steering wheel controller connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard resistance:





NG -- REPLACE SPIRAL CABLE SUB-ASSEMBLY Removal
OK -- Continue to next step.

7. CHECK OUTER MIRROR SWITCH ASSEMBLY (HEATED STEERING WHEEL SWITCH)

(a) Disconnect the outer mirror switch connector.

(b) Measure the voltage according to the value(s) in the table below.





HINT
As the circuit has a diode, perform the measurement in diode test mode, and do not mistaken the polarity.

Standard voltage:





NG -- REPLACE OUTER MIRROR SWITCH ASSEMBLY Removal

OK -- REPLACE HEATED STEERING HEATER CONTROLLER Removal