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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 3) >> Inspection Procedure
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Inspection Procedure

  1. CHECK SEAT HEATER (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   8 

    A: Go to next step 

  2. INSPECT FRONT SEAT HEATER SWITCH (FRONT) (SEE  INSPECTION   ) 

    NG: REPLACE CLIMATE CONTROL SWITCH 

    OK: Go to next step 

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

    HINT:

    1. Disconnect the C20 or C21 blower connector.
    2. Measure the resistance of the wire harness side connector.

    Standard: 

    Driver side 

    TESTER CONNECTION AND SPECIFIED CONDITION - DRIVER SIDE

    Tester Connection Specified Condition
    C20-13 (V5) - C20-9 (VG) Approx. 5 kΩ

    Passenger side 

    TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE

    Tester Connection Specified Condition
    C21-13 (V5) - C21-9 (VG) Approx. 5 kΩ
    Fig 1: Identifying Seat Climate Control Blower Connector Terminals
    G03001138Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  4. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - BODY GROUND) 

    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. Measure the voltage of the wire harness side connector.

    Standard: 

    Driver side 

    TESTER CONNECTION AND SPECIFIED CONDITION - DRIVER SIDE

    Tester Connection Condition Specified Condition
    C20-13 (V5) - Body Ground Ignition switch ON 5 V

    Passenger side 

    TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE

    Tester Connection Condition Specified Condition
    C21-13 (V5) - Body Ground Ignition switch ON 5 V
    Fig 2: Identifying Seat Climate Control Blower Connector Terminals
    G03001139Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER (CLIMATE CONTROL ECU) 

    OK: Go to next step 

  5. INSPECT SEAT CLIMATE CONTROL CONTROLLER (THERMISTOR OF SEATBACK) (SEE  INSPECTION   ) 

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER 

    OK: Go to next step 

  6. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT 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
    C20-3 (TBS) - S34-2 (TBS) Below 1 Ω
    C20-4 (TB5) - S34-3 (TB5) Below 1 Ω

    Passenger side 

    TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE

    Tester Connection Specified Condition
    C21-3 (TBS) - S35-2 (TBS) Below 1 Ω
    C21-4 (TB5) - S35-3 (TB5) Below 1 Ω
    Fig 3: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Controller Connector Terminals
    G03001140Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  7. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - SEAT 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 S48 or S49 controller connector.
    2. Measure the resistance of the wire harness side connector.

    Standard: 

    Driver side 

    TESTER CONNECTION AND SPECIFIED CONDITION - DRIVER SIDE

    Tester Connection Ambient Temperature Specified Condition
    S48-2 (TB5) - S48-1 (TBS) 10°C (50°F) Approx. 3.7 kΩ
    S48-2 (TB5) - S48-1 (TBS) 25°C (77°F) Approx. 2 kΩ
    S48-2 (TB5) - S48-1 (TBS) 30°C (86°F) Approx. 1.7 kΩ

    Passenger side 

    TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE

    Tester Connection Ambient Temperature Specified Condition
    S49-2 (TB5) - S49-1 (TBS) 10°C (50°F) Approx. 3.7 kΩ
    S49-2 (TB5) - S49-1 (TBS) 25°C (77°F) Approx. 2 kΩ
    S49-2 (TB5) - S49-1 (TBS) 30°C (86°F) Approx. 1.7 kΩ

    HINT:

    As the temperature increases, the resistance decreases.

    Fig 4: Identifying Seat Climate Controller Connector Terminals
    G03001141Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER 

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

  8. INSPECT REAR SEAT HEATER SWITCH (REAR) (SEE  INSPECTION   ) 

    NG: REPLACE FRONT SEAT HEATER SWITCH 

    OK: Go to next step 

  9. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - CLIMATE CONTROL SWITCH) 

    HINT:

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

    1. Disconnect the C27 or C29 blower connector.
    2. Measure the resistance of the wire harness side connector.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Specified Condition
    C27-18 (V5) - C27-16 (VG) Approx. 5 kΩ

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C29-18 (V5) - C29-16 (VG) Approx. 5 kΩ
    Fig 5: Identifying Seat Climate Control Blower Connector Terminals
    G03001142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  10. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - BODY GROUND) 

    HINT:

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

    1. Measure the voltage of the wire harness side connector.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Condition Specified Condition
    C27-18 (V5) - Body ground Ignition switch ON, Climate control switch ON 5 V

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Condition Specified Condition
    C29-18 (V5) - Body ground Ignition switch ON, Climate control switch ON 5 V
    Fig 6: Identifying Seat Climate Control Blower Connector Terminals
    G03001143Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER (CLIMATE CONTROL ECU) 

    OK: Go to next step 

  11. INSPECT SEAT CLIMATE CONTROL CONTROLLER (THERMISTOR OF SEATBACK) (SEE  INSPECTION   ) 

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER 

    OK: Go to next step 

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

    HINT:

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

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C28-16 (TBS) - S52-2 (TBS) Below 1 Ω
    C28-7 (TB5) - S52-3 (TB5) Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-16 (TBS) - S54-2 (TBS) Below 1 Ω
    C30-7 (TB5) - S54-3 (TB5) Below 1 Ω
    Fig 7: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Controller Connector Terminals
    G03001144Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  13. INSPECT SEAT CLIMATE CONTROL CONTROLLER (THERMISTOR OF SEAT CUSHION) (SEE  INSPECTION   ) 

    NG: REPLACE SEAT CLIMATE CONTROL CONTROLLER 

    OK: Go to next step 

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

    HINT:

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

    1. Disconnect the C28 or C30 blower connector.
    2. Disconnect the S53 or S55 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
    C28-15 (TCS) - S53-2 (TCS) Below 1 Ω
    C28-6 (TC5) - S53-3 (TC5) Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-15 (TCS) - S55-2 (TCS) Below 1 Ω
    C30-6 (TC5) - S55-3 (TC5) Below 1 Ω
    Fig 8: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate Controller Connector Terminals
    G03001145Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  15. INSPECT SEAT HEATER (THERMISTOR) 

    HINT:

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

    1. Disconnect the S60 or S61 heater connector.
    2. Check the resistance between the terminals of the heater.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH

    Tester Connection Ambient Temperature Specified Condition
    S60-2 (H5) - S60-4 (HS) 10°C (50°F) Approx. 3.7 kΩ
    S60-2 (H5) - S60-4 (HS) 25°C (77°F) Approx. 2 Ω
    S60-2 (H5) - S60-4 (HS) 30°C (86°F) Approx. 1.7 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Ambient Temperature Specified Condition
    S61-2 (H5) - S61-4 (HS) 10°C (50°F) Approx. 3.7 kΩ
    S61-2 (H5) - S61-4 (HS) 25°C (77°F) Approx. 2 Ω
    S61-2 (H5) - S61-4 (HS) 30°C (86°F) Approx. 1.7 Ω
    Fig 9: Identifying Seat Heater Connector Terminals (Thermistor)
    G03001146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT HEATER 

    OK: Go to next step 

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

    HINT:

    When the rear LH indicator is blinking, check the rear LH side connector. When the rear RH indicator is blinking, check the rear right RH 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
    C28-5 (H5) - S60-2 (H5) Below 1 Ω
    C28-14 (HS) - S60-4 (HS) Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C30-5 (H5) - S61-2 (H5) Below 1 Ω
    C30-14 (HS) - S61-4 (HS) Below 1 Ω
    Fig 10: Identifying Seat Climate Control Blower Connector Terminals And Seat Heater Connector Terminals
    G03001147Courtesy 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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