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Inspection Procedure

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: The vehicle is equipped with SRS (Supplemental Restraint System) such as the airbags. Before servicing (including removal or installation of parts), be sure to read the precautionary notice for the SUPPLEMENTAL RESTRAINT SYSTEM .
  1. CHECK ILLUMINATION 
    1. Check if the illumination for the radio and navigation assy, steering pad switch assy, glove box or others (A/C switch, cigarette lighter, etc.) comes on when the light control switch is turned to the HEAD or TAIL position.

    Result: 

    ILLUMINATION CHECK RESULT

    Result Proceed to
    Illumination comes on for all components except steering pad switch. A
    Illumination comes on for all components except radio and navigation assy. B
    No illumination comes on (radio and navigation assy, A/C switch, glove box, etc.). C
    Illumination comes on only for glove box and steering pad switch. D
    1. B: Go to step   6 
    2. C: GO TO LIGHTING SYSTEM (SEE  PROBLEM SYMPTOMS TABLE  ) 
    3. D: GO TO COMBINATION METER SYSTEM (SEE  PROBLEM SYMPTOMS TABLE  ) 

    A: Go to next step. 

  2. INSPECT SPIRAL CABLE SUB-ASSY (ILL+) 
    1. Disconnect the spiral cable sub-assy connector.
    2. Measure the voltage according to the value(s) in the table below.

    Standard: 

    SPIRAL CABLE SUB-ASSY (ILL+) SPECIFIED CONDITION

    Tester connection Condition Specified condition
    ILL+ - Body ground Light control SW TAIL or HEAD 10 to 14 V
    Fig 1: Spiral Cable Sub Assy Connector Front View
    G02577647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  3. INSPECT STEERING PAD SWITCH ASSY 
    Fig 2: Inspecting Steering Pad Switch Assy
    G02577648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the steering pad switch assy connector.
    2. Connect the positive (+) lead to terminal ILL+ and the negative (-) lead to terminal EAU of the steering pad switch assy connector.
    3. Check if the illumination for the steering pad switch assy comes on.

    OK: Illumination for the steering pad switch assy comes on. 

    1. NG: REPLACE  STEERING PAD SWITCH LH 

    OK: Go to next step. 

  4. INSPECT SPIRAL CABLE SUB-ASSY 
    1. Disconnect the steering pad switch assy and spiral cable sub-assy connectors.
    2. Measure the resistance according to the value(s) in the table below.

    Standard: 

    SPIRAL CABLE SUB-ASSY SPECIFIED CONDITION

    Tester connection Specified condition
    EAU - EAU Below 1 Ω
    ILL+ - ILL+ Below 1 Ω
    Fig 3: Inspecting Spiral Cable Sub-Assy
    G02577649Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE  SPIRAL CABLE SUB-ASSY 

    OK: Go to next step. 

  5. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSY - RADIO AND NAVIGATION ASSY) 
    1. Disconnect the connectors from the radio and navigation assy and spiral cable sub-assy.
    2. Measure the resistance according to the value(s) in the table below.

    Standard: 

    SPIRAL CABLE SUB-ASSY - RADIO AND NAVIGATION ASSY TESTER CONNECTION - SPECIFIED CONDITION

    Tester connector Condition Specified condition
    SWG - EAU Always Below 1 Ω
    SWG - Body ground Always 10 kΩ or higher
    Fig 4: Disconnecting Connector From Radio And Navigation Assy
    G02577650Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 5: Spiral Cable Sub Assy Connector Front View
    G02577651Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

  6. INSPECT RADIO AND NAVIGATION ASSY (ILL+) 
    1. Disconnect the radio and navigation assy connector R12.
    2. Measure the voltage according to the value(s) in the table below.

    Standard: 

    RADIO AND NAVIGATION ASSY (ILL+) TESTER CONNECTION - SPECIFIED CONDITION

    Tester connection Condition Specified condition
    ILL+ - Body ground Light control switch TAIL or HEAD 10 to 14 V
    Fig 6: Disconnecting Radio And Navigation Assy Connector R12
    G02577652Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  7. CHECK HARNESS AND CONNECTOR (RADIO AND NAVIGATION ASSY - LIGHT CONTROL RHEOSTAT) 
    1. Disconnect the radio and navigation assy connector R12 and light control rheostat connector R13.
    2. Measure the resistance according to the value(s) in the table below.

    Standard: 

    RADIO AND NAVIGATION ASSY - LIGHT CONTROL RHEOSTAT TESTER CONNECTION - SPECIFIED CONDITION

    Tester connector Condition Specified condition
    ILL-R13-3 Always Below 1 Ω
    ILL-Body ground Always 10 kΩ or higher
    Fig 7: Disconnecting Radio And Navigation Assy Connector R12
    G02577653Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 8: Disconnecting Light Control Rheostat Connector R13
    G02577654Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK 

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

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