LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2005 >> LS 430 >> Repair and Diagnosis >> Body & Frame >> Seats >> Climate Control Seat System - Diagnostics >> Climate Control System Does Not Operate On Rear Side >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

  1. INSPECT FUSE (RR S/HTR) 
    1. Remove the RR S/HTR fuse from the luggage room J/B.
    2. Measure the resistance of the relay.

    Standard: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  2. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - BATTERY) 
    1. Disconnect the C27 or C29 blower connector.
    2. Measure the voltage of the wire harness side connector.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Condition Specified Condition
    C27-10 (IG) - Body ground Ignition switch ON 10 to 14 V

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Condition Specified Condition
    C29-10 (IG) - Body ground Ignition switch ON 10 to 14 V
    Fig 1: Identifying Seat Climate Control Blower Connector Terminals
    G03001170Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   5 

    OK: Go to next step 

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

    Tester Connection Specified Condition
    C27-11 (GND) - Body ground Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C29-11 (GND) - Body ground Below 1 Ω
    Fig 2: Identifying Seat Climate Control Blower Connector Terminals
    G03001171Courtesy 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) 
    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 RH

    Tester Connection Condition Specified Condition
    C27-8 (SW) - Body ground Climate control switch ON Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Condition Specified Condition
    C29-8 (SW) - Body ground Climate control switch ON Below 1 Ω
    Fig 3: Identifying Seat Climate Control Blower Connector Terminals
    G03001172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   10 

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

  5. CHECK WIRE HARNESS (LUGGAGE ROOM J/B ASSY - BODY GROUND) 
    1. Disconnect the LC J/B connector.
    2. Measure the voltage of the J/B connector.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Condition Specified Condition
    LC-3 - Body ground Ignition switch ON 10 to 14 V

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Condition Specified Condition
    LC-4 - Body ground Ignition switch ON 10 to 14 V
    Fig 4: Identifying LC Luggage Room J/B Connector Terminals
    G03001173Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 6 

    OK: REPAIR OR REPLACE HARNESS AND CONNECTOR (LUGGAGE ROOM J/B ASSY - CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU)) 

  6. CHECK WIRE HARNESS (LUGGAGE ROOM J/B ASSY - BATTERY) 
    1. Disconnect the LL J/B connector.
    2. Measure the voltage of the wire harness side connector.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Specified Condition
    LL-1 - Body ground 10 to 14 V
    Fig 5: Identifying LL Luggage Room J/B Ground Harness
    G03001174Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  7. CHECK WIRE HARNESS (LUGGAGE ROOM J/B ASSY - BODY GROUND) 
    1. Disconnect the LA J/B connector.
    2. Measure the resistance of the wire harness side connector.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Specified Condition
    LA-5 - Body ground Below 1 Ω
    Fig 6: Identifying LA Luggage Room J/B Connector Terminals
    G03001175Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  8. INSPECT RELAY (Marking: L-IG1) 
    1. Remove the L-IG1 relay from the luggage room J/B.
    2. Measure the resistance of the relay.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Specified Condition
    3 - 5 10 kΩ or higher
    3 - 5 Below 1Ω (when battery voltage is applied to terminal 1 and 2)
    Fig 7: Identifying L-IG1 Relay Terminals And Circuit
    G03001176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE RELAY 

    OK: Go to next step 

  9. CHECK WIRE HARNESS (LUGGAGE ROOM J/B ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the L14 J/B ECU connector.
    2. Measure the voltage of the wire harness side connector.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Condition Specified Condition
    L14-8 (IG (O)) - Body ground Ignition switch OFF 10 to 14 V
    L14-14 (P-GND) - Body ground Always Below 1Ω
    Fig 8: Identifying L14 Luggage Room J/B ECU Connector Terminals
    G03001177Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE LUGGAGE ROOM JUNCTION BLOCK ASSY 

    OK: REPLACE LUGGAGE ROOM JUNCTION BLOCK ECU 

  10. INSPECT REAR SEAT HEATER SWITCH 
    1. Disconnect the C31 switch connector.
    2. Measure the resistance of the switch.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Switch Condition Specified Condition
    11 (SWL) - 8 (E) OFF 10 kΩ or higher
    11 (SWL) - 8 (E) ON Below 1 Ω
    4 (SWR) - 8 (E) OFF 10 kΩ or higher
    4 (SWR) - 8 (E) ON Below 1 Ω
    Fig 9: Identifying Climate Control Switch Connector Terminals
    G03001178Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE REAR SEAT HEATER SWITCH 

    OK: Go to next step 

  11. CHECK WIRE HARNESS (CLIMATE CONTROL SWITCH - BODY GROUND) 
    1. Disconnect the C31 switch connector.
    2. Measure the resistance of the wire harness side connector.

    Standard: 

    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester Connection Specified Condition
    C31-8 (E) - Body ground Below 1 Ω
    Fig 10: Identifying Climate Control Switch Connector Terminals
    G03001179Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  12. CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL ECU) - CLIMATE CONTROL SWITCH) 
    1. Disconnect the C27 or C29 blower connector.
    2. Disconnect the C31 switch connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard: 

    Rear LH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C31-11 (SWL) - C27-8 (SW) Below 1 Ω

    Rear RH 

    TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH

    Tester Connection Specified Condition
    C31-4 (SWR) - C29-8 (SW) Below 1 Ω
    Fig 11: Identifying Seat Climate Control Blower Connector Terminals And Climate Control Switch Connector Terminals
    G03001180Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

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

scientia non olet · About LEMON Manuals