SEAT HEATER SYSTEM Seat Heater for Front Left Seat does not Operate

DESCRIPTION

When the seat heater switch is operated, the air conditioning amplifier assembly receives the signal via CAN communication line. The air conditioning amplifier assembly receives the signal and operates the front seat heater.

WIRING DIAGRAM

Figure 1. for LHD:

B000ZCHE08

Figure 2. for RHD:

B000ZCHE09

CAUTION / NOTICE / HINT

Note


  • If the battery voltage is low, the seat heater system may not operate. When "High Power Consumption Partial Limit On AC/Heater Operation" is displayed on the multi-information display in the combination meter assembly, inspect the battery, referring to On-vehicle Inspection for the charging system.

    Click here

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

Tech Tips

If the battery voltage is low, the seat heater system may not operate. When "High Power Consumption Partial Limit On AC/Heater Operation" is not displayed on the multi-information display in the combination meter assembly, check the Data List item "Battery Control Count (Body ECU)".

Click here

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      OK
      DTC B14C1 is not output.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (SEAT HEATER CONTROL SUB-ASSEMBLY LH - BATTERY)


    1. B000YY6C03
      *a

      Front view of wire harness connector

      (to Seat Heater Control Sub-assembly LH)

      Disconnect the seat heater control sub-assembly LH connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      w9-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Engine switch off Below 1 V
      w9-1 (+B1) - Body ground Always 11 to 14 V
      w9-8 (+B2) - Body ground Always 11 to 14 V
      Result
      Result Proceed to
      OK (for Standard Seat Type) A
      OK (for Sports Seat Type) B
      NG C

    B

    INSPECT FRONT SEAT CUSHION PAD WITH COVER LH Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  4. INSPECT FRONT SEAT CUSHION HEATER ASSEMBLY LH


    1. Remove the front seat cushion heater assembly LH.

      Click here

    2. Inspect the front seat cushion heater assembly LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEAT CUSHION HEATER ASSEMBLY LH Click here

    OK

  5. INSPECT FRONT SEATBACK SUB-ASSEMBLY LH


    1. Remove the front seatback sub-assembly LH.

      Click here

    2. Inspect the front seatback sub-assembly LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK SUB-ASSEMBLY Click here

    OK

  6. INSPECT SEPARATE TYPE FRONT SEATBACK COVER LH


    1. Remove the separate type front seatback cover LH.

      Click here

    2. Inspect the separate type front seatback cover LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SEPARATE TYPE FRONT SEATBACK COVER LH Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (FRONT SEAT CUSHION HEATER ASSEMBLY LH - SEAT HEATER CONTROL SUB-ASSEMBLY LH AND BODY GROUND)


    1. Disconnect the w5 front seat cushion heater assembly LH connector.

    2. Disconnect the w9 seat heater control sub-assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w5-6 - w9-10 (E) Always Below 1 Ω
      w5-6 or w9-10 (E) - Other terminals and body ground Always 10 kΩ or higher
      w5-1 - w9-7 (Heater Output 1) Always Below 1 Ω
      w5-1 or w9-7 (Heater Output 1) - Other terminals and body ground Always 10 kΩ or higher
      w5-3 - w9-12 (Heater Output 2) Always Below 1 Ω
      w5-3 or w9-12 (Heater Output 2) - Other terminals and body ground Always 10 kΩ or higher
      w5-2 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (FRONT SEAT CUSHION HEATER ASSEMBLY LH - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the w5 front seat cushion heater assembly LH connector.

    2. Disconnect the P56 and P57 air conditioning amplifier assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w5-4 - P56-17 (TSL) Always Below 1 Ω
      w5-4 or P56-17 (TSL) - Other terminals and body ground Always 10 kΩ or higher
      w5-5 - P57-8 (SG-5) Always Below 1 Ω
      w5-5 or P57-8 (SG-5) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (SEAT HEATER CONTROL SUB-ASSEMBLY LH - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the w9 seat heater control sub-assembly LH connector.

    2. Disconnect the P56 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w9-4 (PWM) - P56-15 (SHD+) Always Below 1 Ω
      w9-4 (PWM) or P56-15 (SHD+) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. REPLACE SEAT HEATER CONTROL SUB-ASSEMBLY LH


    1. Temporarily replace the seat heater control sub-assembly LH with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  11. CHECK SEAT HEATER OPERATION


    1. Check the seat heater.

      Click here

      OK
      The seat heater operates normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (SEAT HEATER CONTROL SUB-ASSEMBLY LH WAS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  12. INSPECT FRONT SEAT CUSHION PAD WITH COVER LH


    1. Remove the front seat cushion pad with cover LH.

      Click here

    2. Inspect the front seat cushion pad with cover LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEAT CUSHION PAD WITH COVER LH Click here

    OK

  13. INSPECT FRONT SEATBACK PAD WITH COVER LH


    1. Remove the front seatback pad with cover LH.

      Click here

    2. Inspect the front seatback pad with cover LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK PAD WITH COVER LH Click here

    OK

  14. CHECK HARNESS AND CONNECTOR (FRONT SEAT CUSHION PAD WITH COVER LH - SEAT HEATER CONTROL SUB-ASSEMBLY LH AND BODY GROUND)


    1. Disconnect the w5 front seat cushion pad with cover LH connector.

    2. Disconnect the w9 seat heater control sub-assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w5-6 - w9-10 (E) Always Below 1 Ω
      w5-6 or w9-10 (E) - Other terminals and body ground Always 10 kΩ or higher
      w5-1 - w9-7 (Heater Output 1) Always Below 1 Ω
      w5-1 or w9-7 (Heater Output 1) - Other terminals and body ground Always 10 kΩ or higher
      w5-3 - w9-12 (Heater Output 2) Always Below 1 Ω
      w5-3 or w9-12 (Heater Output 2) - Other terminals and body ground Always 10 kΩ or higher
      w5-2 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  15. CHECK HARNESS AND CONNECTOR (FRONT SEAT CUSHION PAD WITH COVER LH - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the w5 front seat cushion pad with cover LH connector.

    2. Disconnect the P56 and P57 air conditioning amplifier assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      w5-4 - P56-17 (TSL) Always Below 1 Ω
      w5-4 or P56-17 (TSL) - Other terminals and body ground Always 10 kΩ or higher
      w5-5 - P57-8 (SG-5) Always Below 1 Ω
      w5-5 or P57-8 (SG-5) - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 9 Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR