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Home >> Toyota >> 2013 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 129 (Lighting System (Diagnostic Codes & Circuit Tests) (Except Plug-In)) >> Lighting System >> Circuit Tests >> Front Fog Light Circuit >> Procedure
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Front Fog Light Circuit: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test.
    5. Check that the relay operates.
      MAIN BODY

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

      OK

      Front fog light relay operates. (Front fog lights come on.)

    NG → See step   2 

    OK → See step   5 

  2. CHECK OPERATION (TAILLIGHTS) 
    1. Check the operation of the taillights.

      OK

      Taillights operate normally.

    NG → See step   7 

    OK: Go to next step 

  3. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly.
      Fig 1: Identifying Instrument Panel Junction Block Assembly Connector Terminals
      GTY219143Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect a positive (+) lead from the battery to terminal 2E-1.
    3. Connect a negative (-) lead from the battery to terminals A-14 and A-13.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2C-8 - Battery negative Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (BULB - INSTRUMENT PANEL JUNCTION BLOCK AND BODY GROUND) 
    1. Disconnect the 2C instrument panel junction block assembly connector.
    2. Disconnect the C4 or C6 fog light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C4-2 - 2C-8 Always Below 1 Ω
      C6-2 - 2C-8 Always Below 1 Ω
      2C-8 - Body ground Always 10 kΩ or higher
      C4-1 - Body ground Always Below 1 Ω
      C6-1 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   6 

  5. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  6. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL 
  7. GO TO PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE