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Inspection Procedure

  1. INSPECT LUMBAR SUPPORT SWITCH 
    1. Remove the lumbar support switch.
    2. Measure the resistance.

    Standard: 

    Upper side control 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Switch Condition Specified Condition
    5 (B) - 1 (H) HOLD Below 1 Ω
    4 (R) - 6 (E) HOLD Below 1 Ω
    1 (H) - 6 (E) OFF Below 1 Ω
    4 (R) - 6 (E) OFF Below 1 Ω
    1 (H) - 6 (E) RELEASE Below 1 Ω
    4 (R) - 5 (B) RELEASE Below 1 Ω

    Lower side control 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Switch Condition Specified Condition
    2 (H1) - 5 (B) HOLD Below 1 Ω
    3 (R1) - 6 (E) HOLD Below 1 Ω
    2 (H1) - 6 (E) OFF Below 1 Ω
    3 (R1) - 6 (E) OFF Below 1 Ω
    2 (H1) - 6 (E) RELEASE Below 1 Ω
    3 (R1) - 5 (B) RELEASE Below 1 Ω
    Fig 1: Identifying Lumbar Support Switch Connector Terminals
    G03000985Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE LUMBAR SUPPORT SWITCH 

    OK: GO TO NEXT STEP 

  2. INSPECT POWER SEAT MOTOR (SEE  INSPECTION   ) 

    NG: REPLACE POWER SEAT MOTOR 

    OK: GO TO NEXT STEP 

  3. CHECK WIRE HARNESS (LUMBAR SUPPORT SWITCH - POWER SEAT MOTOR AND BODY GROUND) 
    1. Disconnect the P23 switch, connector.
    2. Disconnect the P30 and P31 motor connectors.
    3. Measure the resistance and voltage of the wire harness side connectors.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester connection Specified condition
    P23-1 (H) - P31-1 Below 1 Ω
    P23-4 (R) - P31-2 Below 1 Ω
    P23-2 (H1) - P30-2 Below 1 Ω
    P23-3 (R1) - P30-1 Below 1 Ω
    P23-6 (E) - Body ground Below 1 Ω
    P23-5 (B) - P23-6 (E) 10 to 14 V
    Fig 2: Identifying P23 Lumbar Support Switch Connector Terminals And P30,P31 Power Seat Motor Connector Terminals
    G03000986Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR AND REPLACE HARNESS AND CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON  PROBLEM SYMPTOMS TABLE