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Inspection Procedure

  1. CHECK SEAT ILLUMINATION (OPERATION) 

    HINT:

    The personal lights and interior lights share the same power source. Therefore, if none of them come on, inspect the power source circuit first.

    1. Push the switches for the personal lights.
    2. Check that the personal lights come on.

      OK: Personal lights come on. 

    NG: Go to step  7

    OK: Go to Next Step 

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the intelligent tester on.
    4. Select the item (s) below in the ACTIVE TEST, and check the operation.

      ACTIVE TEST: BODY NO. 3 (Main Body ECU LH) 

      ACTIVE TEST - BODY NO. 3 (MAIN BODY ECU LH)

      Item Test Details Diagnostic Note
      INTERIOR LAMP Interior lights ON / OFF -

      OK: The front and rear interior lights come on. 

      Result 

      RESULT CHART

      Result Proceed to
      Front interior light does not come on A
      Rear interior light does not come on B
      Neither front nor rear interior light comes on C
      OK D

      HINT:

      If the rear interior light comes on normally, but the front interior light does not come on, there is an open circuit in the overhead J/B.

    A: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH) 

    B: Go to step 3 

    C: Go to step  5

    D: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  3. INSPECT REAR DOME LIGHT ASSEMBLY (REAR INTERIOR LIGHT) 
    Fig 1: Identifying R8 Rear Dome Light Connector Terminals
    G05320392Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the rear dome light assembly.
    2. Connect the (+) lead from the battery to terminal 2 and the (-) lead to terminal 4, and then check that the interior light comes on.

      OK: The interior light comes on. 

    NG: REPLACE REAR DOME LIGHT ASSEMBLY 

    OK: Go to Next Step 

  4. CHECK HARNESS AND CONNECTOR (OVERHEAD J/B - REAR DOME LIGHT ASSEMBLY) 
    1. Disconnect the R8 rear dome light assembly connector.
    2. Disconnect the R5 overhead J/B connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R8-2 (ILLB) - R5-4 (ILLB) Always Below 1 Ω
      R8-4 (RILL) - R5-33 (RILL) Always Below 1 Ω
      R8-2 (ILLB) - Body ground Always 10 kΩ or higher
      R8-4 (RILL) - Body ground Always 10 kΩ or higher
      Fig 2: Identifying R8 Rear Dome Light Assembly Connector Terminals
      G05320393Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH) 

  5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B) 
    1. Disconnect the Q1 main body ECU LH connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      Q1-2 (ILE) - Body ground Always 10 to 14 V
      Fig 3: Identifying Q1 Main Body ECU LH Connector Terminals
      G05320394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 6 

    OK: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH) 

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B) 
    1. Disconnect the Q1 main body ECU LH connector.
    2. Disconnect the R5 overhead J/B connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      Q1-2 (ILE) - R5-13 (ILL) Always Below 1 Ω
      Q1-2 (ILE) - Body ground Always 10 kΩ or higher
      Fig 4: Identifying Q1 Main Body ECU LH Connector Terminals
      G05320395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH) 

  7. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 
    1. Disconnect the R5 overhead J/B connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R5-1 (+B1) - Body ground Always 10 to 14 V
      Fig 5: Identifying R5 Overhead J/B Connector Terminals
      G05320396Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)