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

DESCRIPTION

When the seat heater switch on air conditioning control assembly is operated, the seat heater control sub-assembly LH receives the signal. The seat heater control sub-assembly LH receives the signal and operates the front seat heater.

WIRING DIAGRAM


  1. for TMC Made

    B008MB3E03

  2. for TMMT Made

    B008MB3E04

CAUTION / NOTICE / HINT

Note


  • If the battery voltage is low, the seat heater system may not operate. Refer to Data List for the power steering system.

    Click here

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

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 B14B5 is not output.
      Result
      Result Proceed to
      OK (for TMC Made) A
      OK (for TMMT Made) B
      NG C

    B

    CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - SEAT HEATER CONTROL SUB-ASSEMBLY LH) Click here

    C

    GO TO DIAGNOSTIC TROUBLE CODE CHART Click here

    A

  3. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - SEAT HEATER CONTROL SUB-ASSEMBLY LH)


    1. B008L3CC07
      *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 Switch Condition Specified Condition
      Z2-1 (+B1) - Body ground Ignition switch ON 11 to 14 V
      Ignition switch off Below 1 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the Z2 seat heater control sub-assembly LH connector.

    2. Disconnect the Z1 front seat cushion heater assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Z2-7 (HTR1) - Z1-1 Always Below 1 Ω
      Z2-9 (THR+) - Z1-4 Always Below 1 Ω
      Z2-5 (THR-) - Z1-5 Always Below 1 Ω
      Z2-10 (E) - Z1-6 Always Below 1 Ω
      Z1-2 - Body ground Always Below 1 Ω
      Z2-7 (HTR1) or Z1-1 - Body ground Always 10 kΩ or higher
      Z2-9 (THR+) or Z1-4 - Body ground Always 10 kΩ or higher
      Z2-5 (THR-) or Z1-5 - Body ground Always 10 kΩ or higher
      Z2-10 (E) or Z1-6 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. 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

  6. INSPECT FRONT SEATBACK HEATER ASSEMBLY LH


    1. Remove the front seatback heater assembly LH.

      Click here

    2. Inspect the front seatback heater assembly LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK HEATER ASSEMBLY LH Click here

    OK

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


    1. Disconnect the F61 seat heater switch (air conditioning control assembly) connector.

    2. Disconnect the Z2 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
      F61-12 (SW) - Z2-2 (SWR) Always Below 1 Ω
      F61-6 (RV) - Z2-3 (VOL) Always Below 1 Ω
      F61-12 (SW) or Z2-2 (SWR) - Body ground Always 10 kΩ or higher
      F61-6 (RV) or Z2-3 (VOL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. REPLACE SEAT HEATER CONTROL SUB-ASSEMBLY LH


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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK SEAT HEATER SYSTEM OPERATION


    1. Check that the seat heater system is operated normally.

      OK
      The seat heater system is operated normally.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  10. REPLACE SEAT HEATER SWITCH (AIR CONDITIONING CONTROL ASSEMBLY)


    1. Temporarily replace the seat heater switch (air conditioning control assembly) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  11. CHECK SEAT HEATER SYSTEM OPERATION


    1. Check that the seat heater system is operated normally.

      OK
      The seat heater system is operated normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (SEAT HEATER SWITCH (AIR CONDITIONING CONTROL ASSEMBLY) WAS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  12. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - SEAT HEATER CONTROL SUB-ASSEMBLY LH)


    1. B008L3CC08
      *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 Switch Condition Specified Condition
      Z2-8 (+B1) - Body ground Ignition switch ON 11 to 14 V
      Ignition switch off Below 1 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the Z2 seat heater control sub-assembly LH connector.

    2. Disconnect the Z1 front seat cushion heater assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Z2-1 (HTR1) - Z1-1 Always Below 1 Ω
      Z2-6 (THR+) - Z1-4 Always Below 1 Ω
      Z2-11 (THR-) - Z1-5 Always Below 1 Ω
      Z2-7 (E) - Z1-6 Always Below 1 Ω
      Z1-2 - Body ground Always Below 1 Ω
      Z2-1 (HTR1) or Z1-1 - Body ground Always 10 kΩ or higher
      Z2-6 (THR+) or Z1-4 - Body ground Always 10 kΩ or higher
      Z2-11 (THR-) or Z1-5 - Body ground Always 10 kΩ or higher
      Z2-7 (E) or Z1-6 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. 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

  15. INSPECT FRONT SEATBACK HEATER ASSEMBLY LH


    1. Remove the front seatback heater assembly LH.

      Click here

    2. Inspect the front seatback heater assembly LH.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK HEATER ASSEMBLY LH Click here

    OK

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


    1. Disconnect the F61 seat heater switch (air conditioning control assembly) connector.

    2. Disconnect the Z2 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
      F61-12 (SW) - Z2-3 (SWR) Always Below 1 Ω
      F61-6 (RV) - Z2-4 (VOL) Always Below 1 Ω
      F61-12 (SW) or Z2-3 (SWR) - Body ground Always 10 kΩ or higher
      F61-6 (RV) or Z2-4 (VOL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  17. REPLACE SEAT HEATER CONTROL SUB-ASSEMBLY LH


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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  18. CHECK SEAT HEATER SYSTEM OPERATION


    1. Check that the seat heater system is operated normally.

      OK
      The seat heater system is operated normally.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  19. REPLACE SEAT HEATER SWITCH (AIR CONDITIONING CONTROL ASSEMBLY)


    1. Temporarily replace the seat heater switch (air conditioning control assembly) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  20. CHECK SEAT HEATER SYSTEM OPERATION


    1. Check that the seat heater system is operated normally.

      OK
      The seat heater system is operated normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (SEAT HEATER SWITCH (AIR CONDITIONING CONTROL ASSEMBLY) WAS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here