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

DTC Code DTC Name
Steering Wheel does not Heat Up When Heated Steering Wheel Switch is Pressed

DESCRIPTION

The heater unit heats the steering wheel when the steering heater switch is operated.

Tip:

  • The heater 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 heater unit.

WIRING DIAGRAM

C221421E01

PROCEDURE

  1. CHECK STEERING HEATER SWITCH (LED OPERATION)

    1. C221135

      Check the illumination condition of the LED.

      Result

      LED

      Condition

      Proceed to

      Blinks

      Engine switch on (IG)

      Heated steering wheel switch is pushed and held continuously for 10 seconds or more

      A

      Illuminates

      Engine switch on (IG)

      Heated steering wheel switch is pushed

      B

      Does not blink or illuminate

      Engine switch on (IG)

      Heated steering wheel switch is pushed
    B

    INSPECT STEERING WHEEL ASSEMBLY (HEATER, THERMOSTAT)Click here

    A

  2. INSPECT STEERING WHEEL ASSEMBLY (THERMISTOR)

    1. Disconnect the steering wheel controller connector.

    2. C145883C01

      *a

      Front view of wire harness connector

      (to Heated Steering Wheel Controller)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1 (TH2) - 3 (TH1)

      25°C (77°F)

      9.7 to 10.3 kΩ

      Result

      Result

      OK

      NG
    NG

    REPLACE STEERING WHEEL ASSEMBLY

    Click hereClick hereClick here

    OK

  3. INSPECT STEERING WHEEL ASSEMBLY (HEATER, THERMOSTAT)

    1. Disconnect the steering wheel controller connector.

    2. C145883C02

      *a

      Front view of wire harness connector

      (to Heated Steering Wheel Controller)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      2 (SH2) - 4 (SH1)

      20°C (68°F)

      1.88 to 2.26 Ω

      Result

      Result

      OK

      NG
    NG

    REPLACE STEERING WHEEL ASSEMBLY

    Click hereClick hereClick here

    OK

  4. CHECK HARNESS AND CONNECTOR (STEERING HEATER SWITCH - SPIRAL CABLE)

    1. Disconnect the G66 steering heater switch connector.

    2. Disconnect the G30 spiral cable connector.

    3. C261405C01

      *a

      Front view of wire harness connector

      (to Steering Heater Switch)

      *b

      Front view of wire harness connector

      (to Spiral Cable)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G66-5 (INDC) - G30-1 (BTM)

      Always

      Below 1 Ω

      G66-9 (RC) - G30-3 (ETM)

      Always

      Below 1 Ω

      G30-2 (EHT) - Body ground

      Always

      Below 1 Ω

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      G30-4 (BHT) - Body ground

      Engine switch on (IG)

      11 to 14 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR

    OK

  5. INSPECT SPIRAL CABLE SUB-ASSEMBLY

    Note:

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

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

    1. Disconnect the G30 spiral cable connector.

    2. Disconnect the heated steering wheel controller connector.

    3. C261406C01

      *a

      Component without harness connected

      (Spiral Cable)

      *b

      Front view of harness connector

      (to Heated Steering Wheel Controller)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1 (CCU) - G30-1 (BTM)

      Always

      Below 1 Ω

      2 (CCV) - G30-3 (ETM)

      Always

      Below 1 Ω

      3 (CCX) - G30-2 (EHT)

      Always

      Below 1 Ω

      4 (CCW) - G30-4 (BHT)

      Always

      Below 1 Ω

      Result

      Result

      OK

      NG
    NG

    REPLACE SPIRAL CABLE SUB-ASSEMBLY

    Click here

    OK

  6. CHECK STEERING HEATER SWITCH

    1. Disconnect the steering heater switch connector.

    2. C221426C01

      *a

      Component without harness connected

      (to Steering Heater Switch)

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

      Tip:

      As the circuit has a diode, perform the measurement in diode test mode and make sure that the polarity is correct.

      Standard Resistance

      Tester ConnectionPositive (+) tester probe - Negative (-) tester probe

      Switch Condition

      Specified Condition

      G66-1 (IG) - G66-4 (RC)

      Heated steering wheel switch is pushed

      Below 1.25 V

      Result

      Result

      OK

      NG
    OK

    REPLACE HEATED STEERING HEATER CONTROLLER

    Click hereClick hereClick here

    NG

    REPLACE STEERING HEATER SWITCH