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Home >> Lexus >> 2005 >> LS 430 >> Repair and Diagnosis >> Body & Frame >> Seats >> Climate Control Seat System - Diagnostics >> Climate Control Does Not Operate (Blinking Pattern 1) >> Inspection Procedure
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Inspection Procedure

  1. CHECK CLIMATE CONTROL SWITCH (INDICATOR) 
    1. Check that the climate control indicator is blinking.

    Result: 

    RESULT REFERENCE

    Result Proceed to
    Front climate control switch indicator is blinking A
    Rear climate control switch indicator is blinking B

    B: Go to step   5 

    A: Go to next step 

  2. CHECK SEAT CLIMATE CONTROL CONTROLLER (SEATBACK) 

    HINT:

    When the driver side indicator is blinking, check the driver side connector. When the passenger side indicator is blinking, check the passenger side connector.

    1. Disconnect the S34 or S35 controller connector.
    2. Connect the wire harness to terminal 4 (TDB-) and 5 (TDB+) of the wire harness side connector.
    3. Turn the ignition switch ON.
    4. Turn the climate control switch ON, then check that the climate control indicator continues blinking.

    Result: 

    RESULT REFERENCE

    Result Proceed to
    Indicator continues blinking A
    Indicator turns off B
    Fig 1: Checking Seat Climate Control Controller (Seatback)
    G03001124Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: REPLACE SEAT CLIMATE CONTROL CONTROLLER (SEATBACK) 

    A: Go to next step 

  3. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - CLIMATE CONTROLLER) 

    HINT:

    When the driver side indicator is blinking, check the driver side connector. When the passenger side indicator is blinking, check the passenger side connector.

    1. Disconnect the C20 or C21 blower connector.
    2. Disconnect the S34 or S35 controller connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard: 

    Driver side 

    TESTER CONNECTION AND SPECIFIED CONDITION - DRIVER SIDE

    Tester Connection Specified Condition
    C20-1 (TDB-) - S34-4 (TDB-) Below 1 Ω
    C20-1 (TDB-) - Body ground 10 kΩ or higher
    C20-14 (TDB+) - S34-5 (TDB+) Below 1 Ω
    C20-14 (TDB+) - Body ground 10 kΩ or higher
    C20-1 (TDB-) - C20-14 (TDB+) 10 kΩ or higher

    Passenger side 

    TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE

    Tester Connection Specified Condition
    C21-1 (TDB-) - S35-4 (TDB-) Below 1 Ω
    C21-1 (TDB-) - Body ground 10 kΩ or higher
    C21-14 (TDB+) - S35-5 (TDB+) Below 1 Ω
    C21-14 (TDB+) - Body ground 10 kΩ or higher
    C21-1 (TDB-) - C21-14 (TDB+) 10 kΩ or higher
    Fig 2: Identifying Seat Climate Control Blower Connector And Seat Climate Controller Connector
    G03001125Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  4. CHECK SEAT CLIMATE CONTROL CONTROLLER (SEAT CUSHION) 

    HINT:

    When the driver side indicator is blinking, check the driver side connector. When the passenger side indicator is blinking, check the passenger side connector.

    1. Disconnect the S48 or S49 connector.
    2. Connect terminal 3 (TDC+) and 6 (TDC-) of the climate control ECU connector, as shown in the illustration.
    3. Turn the ignition switch ON.
    4. Turn the climate control switch ON, and then check that the climate control switch indicator turns off.

    OK: The indicator turns off 

    Fig 3: Checking Seat Climate Control Controller (Seat Cushion)
    G03001126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT CLIMATE CONTROL BLOWER REPAIR SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) 

    OK: REPLACE SEAT CLIMATE CONTROLLER (SEAT CUSHION) 

  5. CHECK SEAT CLIMATE CONTROL CONTROLLER (SEATBACK) 

    HINT:

    When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is blinking, check the rear RH connector.

    1. Disconnect the S52 or S54 controller connector.
    2. Connect the wire harness to terminal 4 (TDB-) and 5 (TDB+) of the wire harness side connector.
    3. Turn the ignition switch ON.
    4. Turn the climate control switch ON, and then check that the climate control indicator continues blinking.

    Result: 

    RESULT REFERENCE

    Result Proceed to
    Indicator continues blinking A
    Indicator turns off B
    Fig 4: Checking Seat Climate Control Controller (Seatback)
    G03001127Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: REPLACE SEAT CLIMATE CONTROL CONTROLLER (SEATBACK) 

    A: Go to next step 

  6. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT CLIMATE CONTROLLER (SEATBACK)) 

    HINT:

    When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is blinking, check the rear RH connector.

    1. Disconnect the C28 or C30 blower connector.
    2. Disconnect the S52 or S54 controller connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Specified Condition
    C28-2 (TDB-) - S52-4 (TDB-) Below 1 Ω
    C28-2 (TDB-) - Body ground 10 kΩ or higher
    C28-1 (TDB+) - S52-5 (TDB+) Below 1 Ω
    C28-1 (TDB+) - Body ground 10 kΩ or higher
    C28-1 (TDB+) - C28-2 (TDB-) 10 kΩ or higher

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-2 (TDB-) - S54-4 (TDB-) Below 1 Ω
    C30-2 (TDB-) - Body ground 10 kΩ or higher
    C30-1 (TDB+) - S54-5 (TDB+) Below 1 Ω
    C30-1 (TDB+) - Body ground 10 kΩ or higher
    C30-1 (TDB+) - S30-2 (TDB-) 10 kΩ or higher
    Fig 5: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Controller Connector Terminals
    G03001128Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  7. CHECK SEAT CLIMATE CONTROL CONTROLLER (SEAT CUSHION) 

    HINT:

    When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is blinking, check the rear RH connector.

    1. Disconnect the S53 or S55 blower connector.
    2. Connect the wire harness to terminal 5 (TDC+) and 4 (TDC-) of the wire harness side connector, as shown in the illustration.
    3. Turn the ignition switch ON.
    4. Turn the climate control switch ON, and then check that the climate control indicator turns off.

    OK: The indicator turns off 

    Fig 6: Checking Seat Climate Control Controller (Seat Cushion)
    G03001129Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 8 

    OK: REPLACE SEAT CLIMATE CONTROLLER (SEAT CUSHION) 

  8. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT CLIMATE CONTROLLER (SEAT CUSHION)) 

    HINT:

    When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is blinking, check the rear RH connector.

    1. Disconnect the C28 or C30 blower connector.
    2. Disconnect the S53 or S55 controller connector.
    3. Measure the resistance of between the wire harness side connectors.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Specified Condition
    C28-11 (TDC-) - S53-4 (TDC-) Below 1 Ω
    C28-11 (TDC-) - Body ground 10 kΩ or higher
    C28-10 (TDC+) - S53-5 (TDC+) Below 1 Ω
    C28-10 (TDC+) - Body ground 10 kΩ or higher
    C28-10 (TDC+) - C28-11 (TDC-) 10 kΩ or higher

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-11 (TDC-) - S55-4 (TDC-) Below 1 Ω
    C30-11 (TDC-) - Body ground 10 kΩ or higher
    C30-10 (TDC+) - S55-5 (TDC+) Below 1 Ω
    C30-10 (TDC+) - Body ground 10 kΩ or higher
    C30-10 (TDC+) - C30-11 (TDC-) 10 kΩ or higher
    Fig 7: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Controller Connector Terminals
    G03001130Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  9. CHECK SEAT HEATER (SEATBACK) (SEE  INSPECTION   ) 

    NG: REPLACE REAR SEATBACK PAD 

    OK: Go to next step 

  10. INSPECT SEAT HEATER (SEAT CUSHION) (SEE  INSPECTION   ) 

    NG: REPLACE SEAT CUSHION PAD 

    OK: Go to next step 

  11. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT HEATER) 

    HINT:

    When the indicator of rear left side is blinking, check the rear left side connector. When the indicator of rear right side is blinking, check the rear right side connector.

    1. Disconnect the C28 or C30 blower connector.
    2. Disconnect the S60 or S61 heater connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Specified Condition
    C28-8 (E) - S60-3 (E) Below 1 Ω
    C28-8 (E) - S60-1 (B) 10 kΩ or higher
    C28-18 (B) - S60-1 (B) Below 1 Ω
    C28-18 (B) - S60-3 (E) 10 kΩ or higher

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-8 (E) - S61-3 (E) Below 1 Ω
    C30-8 (E) - S61-1 (B) 10 kΩ or higher
    C30-18 (B) - S61-1 (B) Below 1 Ω
    C30-18 (B) - S61-3 (E) 10 kΩ or higher
    Fig 8: Identifying Seat Climate Control Blower Connector Terminals And Seat Heater Connector Terminals
    G03001131Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  12. INSPECT SEAT CLIMATE CONTROL BLOWER (FAN MOTOR OF SEATBACK) (SEE  INSPECTION   ) 

    NG: REPLACE SEAT CLIMATE CONTROL BLOWER (SEATBACK) 

    OK: Go to next step 

  13. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT CLIMATE FAN MOTOR) 

    HINT:

    When the indicator of rear left side is blinking, check the rear left side connector. When the indicator of rear right side is blinking, check the rear right side connector.

    1. Disconnect the C27 or C29 blower connector.
    2. Disconnect the S56 or S58 motor connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Specified Condition
    C27-3 (BBS) - S56-3 (BBS) Below 1 Ω
    C27-3 (BBS) - S56-2 (BFB(+)) 10 kΩ or higher
    C27-2 (BFB+) - S56-2 (BFB(+)) Below 1 Ω
    C27-2 (BFB+) - S56-3 (BBS) 10 kΩ or higher

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C29-3 (BBS) - S58-3 (BBS) Below 1 Ω
    C29-3 (BBS) - S58-2 (BFB(+)) 10 kΩ or higher
    C29-2 (BFB+) - S58-2 (BFB(+)) Below 1 Ω
    C29-2 (BFB+) - S58-3 (BBS) 10 kΩ or higher
    Fig 9: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Fan Motor Connector Terminals
    G03001132Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: REPLACE SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) 

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