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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
  1. PERFORM ACTIVE TEST BY TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test.
    5. Check the operation.

      Main Body (Main Body ECU) 

      CONTROL RANGE CHART

      Tester Display Test Part Control Range Diagnostic Note
      Front Fog Light Relay Front fog light relay ON / OFF -

      OK: 

      Front fog light comes on. 

    OK:  Go to step  9

    NG: Go to next step 

  2. CHECK TAILLIGHT 
    1. Check that the taillight comes on when the light control switch is on (TAIL).

      OK: 

      Taillight comes on. 

    NG:  GO TO TAILLIGHT RELAY CIRCUIT 

    OK: Go to next step 

  3. INSPECT FUSE (FR FOG) 
    1. Remove the FR FOG fuse from the instrument panel junction block.
    2. Measure the resistance of the fuses.

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  4. INSPECT FOG LIGHT BULB 
    1. Remove the fog light bulb.
    2. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, then check that the bulb illuminates.

      OK: 

      Bulb illuminates. 

      Fig 1: Identifying Fog Light Bulb Connector Terminals
      G05585919Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FOG LIGHT BULB 

    OK: Go to next step 

  5. INSPECT FRONT FOG LIGHT RELAY (Marking: FR FOG) 
    1. Remove the front fog light relay from the No. 6 relay block.
    2. Measure the resistance of the relay.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (Battery voltage applied to terminals 1 and 2)
      Fig 2: Inspecting Front Fog Light Relay
      G05585920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT FOG LIGHT RELAY 

    OK: Go to next step 

  6. CHECK WIRE HARNESS (BATTERY - MAIN BODY ECU) 
    1. Disconnect the E17 ECU connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      STANDARD VOLTAGE

      Tester Connection Condition Specified Condition
      E17-17 (FFGO) - Body ground Light control switch on (TAIL) 10 to 14 V
      Fig 3: Identifying E17 ECU Connector Terminal
      G05585921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  7. CHECK WIRE HARNESS (FRONT FOG LIGHT RELAY - BATTERY) 
    1. Remove the front fog light relay from the No. 6 relay block.
    2. Measure the voltage of the relay block.

      standard voltage 

      STANDARD VOLTAGE

      Tester Connection Specified Condition
      No. 6 relay block front fog light relay terminal 5 - Body ground 10 to 14 V
      Fig 4: Identifying Front Fog Light Relay
      G05585922Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  8. CHECK WIRE HARNESS (FRONT FOG LIGHT RELAY - FRONT FOG LIGHT AND BODY GROUND) 
    1. Remove the front fog light relay from the No. 6 relay block.
    2. Disconnect the A11 and A28 front fog light connectors.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Specified Condition
      No. 6 relay block front fog light relay terminal 3 -A11 -2 Below 1 Ω
      No. 6 relay block front fog light relay terminal 3 or A11-2 - Body ground 10 kΩ or higher
      No. 6 relay block front fog light relay terminal 3 - A28-2 Below 1 Ω
      No. 6 relay block front fog light relay terminal 3 or A28-2 - Body ground 10 kΩ or higher
      A11-1 - Body ground Below 1 Ω
      A28-1 - Body ground Below 1 Ω
      Fig 5: Identifying A11 And A28 Front Fog Light Connector Terminals
      G05585923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK (MAIN BODY ECU) 

  9. CHECK WIRE HARNESS (DIMMER SWITCH - MAIN BODY ECU AND BODY GROUND) 
    Fig 6: Identifying Headlight Dimmer Switch And Main Body ECU Connector Terminals
    G05585924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E12 headlight dimmer switch connector.
    2. Disconnect the E17 main body ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Specified Condition
      E17-13 (FFOG) - E12-4 (BFG) Below 1 Ω
      E17-13 (FFOG) or E12-4 (BFG) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  10. INSPECT FOG LIGHT SWITCH 
    1. Remove the headlight dimmer switch.
    2. Measure the resistance of the switch.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      4 (BFG) - 3 (LFG) Fog light switch OFF 10 kΩ or higher
      4 (BFG) - 3 (LFG) Fog light switch ON Below 1 Ω
      Fig 7: Inspecting Fog Light Switch
      G05585925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY 

    OK: REPAIR OR REPLACE HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH - BODY GROUND) 

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