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

DESCRIPTION

Click here

WIRING DIAGRAM

B003ZDPE05

CAUTION / NOTICE / HINT

Tech Tips


  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • The steering wheel heater unit is built into the steering wheel assembly which cannot be disassembled. Therefore, when the steering wheel heater unit has a malfunction, replace the steering wheel assembly.

PROCEDURE


  1. INSPECT STEERING WHEEL HEATER UNIT (THERMISTOR/HEATER/THERMOSTAT)


    1. B003ZEAC05
      *a

      Front view of wire harness connector

      (to Steering Wheel Heater Control Assembly)

      Disconnect the B steering wheel heater control assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B-1 (TH1) - B-2 (TH2) 10 to 30°C (50 to 86°F) 8.132 to 18.43 kΩ
      B-4 (SH1) - B-3 (SH2) 20°C (68°F) 1.89 to 2.25 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STEERING WHEEL ASSEMBLY Click here

    OK

  2. INSPECT SPIRAL CABLE SUB-ASSEMBLY


    1. Check the connectors and cables of the spiral cable sub-assembly.

      OK
      There are no defects such as scratches, cracks, dents or damage on the connectors or cables.

    2. Disconnect the F62 and z7 spiral cable sub-assembly connectors.

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

      B003YYKC08
      *a Component without harness connected (Spiral Cable Sub-assembly) - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      z7-1 (BTM) - F62-1 (BTM) Always 3 Ω or less
      z7-2 (ETM) - F62-3 (ETM) Always 3 Ω or less
      z7-3 (EHT) - F62-2 (EHT) Always Below 0.1 Ω
      z7-4 (BHT) - F62-4 (BHT) Always Below 0.1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SPIRAL CABLE SUB-ASSEMBLY Click here

    OK

  3. CHECK STEERING HEATER SWITCH


    1. B003ZWYC03
      *a Component without harness connected (Steering Heater Switch)

      Disconnect the F45 steering heater switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F45-3 (IG) - F45-6 (IN) Steering heater switch is pushed Below 1 Ω
      F45-3 (IG) - F45-6 (IN) Steering heater switch is not pushed 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STEERING HEATER SWITCH Click here

    OK

  4. CHECK IG1 NO. 4 RELAY (STEERING HEATER RELAY)


    1. B003YYOC01
      *1 IG1 NO. 4 Relay (Steering Heater Relay)

      Remove the IG1 No. 4 relay (steering heater relay) from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 Voltage is applied between terminals 1 and 2 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE IG1 NO. 4 RELAY (STEERING HEATER RELAY)

    OK

  5. CHECK HARNESS AND CONNECTOR (STEERING HEATER SWITCH - SPIRAL CABLE SUB-ASSEMBLY)


    1. Disconnect the F45 steering heater switch connector.

    2. Disconnect the F62 spiral cable sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F45-7 (+) - F62-1 (BTM) Always Below 1 Ω
      F45-6 (IN) - F62-3 (ETM) Always Below 1 Ω
      F45-7 (+) or F62-1 (BTM) - Body ground Always 10 kΩ or higher
      F45-6 (IN) or F62-3 (ETM) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (IG1 NO. 4 RELAY (STEERING HEATER RELAY) - SPIRAL CABLE SUB-ASSEMBLY)


    1. Remove the IG1 No. 4 relay (steering heater relay) from the No. 2 engine room relay block.

    2. Disconnect the F62 spiral cable sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - F62-4 (BHT) Always Below 1 Ω
      3 or F62-4 (BHT) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (STEERING HEATER SWITCH POWER SOURCE)


    1. Disconnect the F45 steering heater switch connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F45-3 (IG) - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (IG1 NO. 4 RELAY (STEERING HEATER RELAY) POWER SOURCE)


    1. Remove the IG1 No. 4 relay (steering heater relay) from the No. 2 engine room relay block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      5 - Body ground Always 11 to 14 V
      1 - Body ground Ignition switch ON 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSEMBLY BODY GROUND)


    1. Disconnect the F62 spiral cable sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F62-2 (EHT) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE STEERING WHEEL HEATER CONTROL ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR