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Inspection Procedure

  1. READ VALUE OF HAND-HELD TESTER (LIGHT RHEOSTAT SIGNAL) 
    1. Operate the hand-held tester according to the steps on the display and select the "DATA LIST".

    METER: 

    DATA LIST REFERENCE

    Item Measurement Item/ Range (Display) Normal Condition Diagnostic Note
    LIGHT RHEOSTAT Light control rheostat / Min.: 0, Max.: 255 Light control rheostat switch is Dark (0) --> Bright (255) -

    OK: 

    Light control can be changed within the specified range by actual operation. 

    NG: Go to step 2 

    OK: REPLACE COMBINATION METER ASSY (SEE  OVERHAUL  ) 

  2. READ VALUE OF HAND-HELD TESTER (LIGHT RHEOSTAT SIGNAL) 
    1. Operate the hand-held tester according to the steps on the display and select the "DATA LIST".

    BODY No.2: 

    DATA LIST REFERENCE

    Item Measurement Item/ Range (Display) Normal Condition Diagnostic Note
    LIGHT RHEOSTAT Light control rheostat / Min.: 0, Max.: 255 Light control rheostat switch is Dark (0) --> Bright (255) -

    OK: 

    Light control can be changed within the specified range by actual operation 

    NG: Go to step   5 

    OK: GO TO NEXT STEP 

  3. CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK -COMBINATION METER ASSY) (SEE  HOW TO PROCEED WITH TROUBLESHOOTING  ) 
    1. Disconnect the C12 and D6 connectors.
    2. Measure the resistance according to the value (s) in the table below.

    Standard 

    C12 AND D6 CONNECTORS RESISTANCE SPECIFICATIONS

    Tester Connection Condition Specified Condition
    C12-16 - D6-15 Always Below 1 Ω
    C12-16 - Body ground Always 10 kΩ or higher
    Fig 1: Identifying Light Control Rheostat Connector Terminals
    G03000721Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO NEXT STEP 

  4. REPLACE DRIVER SIDE JUNCTION BLOCK 

    OK: 

    Normal operation 

    NG: REPLACE COMBINATION METER ASSY (SEE  OVERHAUL  ) 

    OK: END 

  5. INSPECT LIGHT CONTROL RHEOSTAT 
    1. Disconnect the light control rheostat connector.
    2. Measure the voltage according to the value (s) in the table below.

    Standard 

    LIGHT CONTROL RHEOSTAT VOLTAGE SPECIFICATIONS

    Terminal No Condition Specified condition
    1 - 2 Rheostat knob turned fully clockwise Approx. 0 kΩ
    1 - 2 Rheostat knob turned fully counterclockwise Approx. 10 +/- 2 kΩ
    1 - 3 Always Approx. 10 +/- 2 kΩ
    4 - 1,3 Rheostat knob turned fully counterclockwise 10 kΩ or higher
    4 - 1,3 Rheostat knob turned to fully clockwise Below 1 Ω

    NG: REPLACE LIGHT CONTROL RHEOSTAT 

    Fig 2: Identifying D6 And R4 Connector Terminals
    G03000722Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. CHECK HARNESS AND CONNECTOR (LIGHT CONTROL RHEOSTAT - DRIVER SIDE JUNCTION BLOCK) (SEE  HOW TO PROCEED WITH TROUBLESHOOTING  ) 
    1. Disconnect the D6 and R4 connectors.
    2. Measure the resistance according to the value (s) in the table below.

    Standard 

    D6 AND R4 CONNECTORS RESISTANCE SPECIFICATIONS

    Tester Connection Condition Specified Condition
    D6-20 - R4-3 Always Below 1 Ω
    D6-22 - R4-2 Always Below 1 Ω
    D6-21 - R4-1 Always Below 1 Ω
    D6-1 - R4-4 Always Below 1 Ω
    R4-3 - Body ground Always 10 kΩ or higher
    R4-2 - Body ground Always 10 kΩ or higher
    R4-1 - Body ground Always 10 kΩ or higher
    R4-4 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Identifying Terminal C12-19
    G03000723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  7. REPLACE DRIVER SIDE JUNCTION BLOCK 

    OK: 

    Normal operation 

    NG: REPLACE COMBINATION METER ASSY (SEE  OVERHAUL  ) 

    OK: END 

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