LIGHTING SYSTEM Front Fog Light Circuit

DESCRIPTION

The main body ECU receives a front fog light switch information signal from the light control switch (front fog switch), and illuminates the front fog lights.

WIRING DIAGRAM

A003E7FE04

INSPECTION PROCEDURE

Tech Tips

Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (FRONT FOG LIGHT)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Main Body / Active Test / Front Fog Light.

    5. Check that the front fog lights turn on/off.

      Main Body
      Tester Display Test Part Control Range Diagnostic Note
      Front Fog Light Relay Front fog light ON or OFF -
      OK
      Front fog lights turn on/off.

    NG

    CHECK HARNESS AND CONNECTOR (FRONT FOG LIGHT BULB - BATTERY) Click here

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. CHECK HARNESS AND CONNECTOR (FRONT FOG LIGHT BULB - BATTERY)

    A003CYSE01
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Front Fog Light Bulb)
    *2 for LH
    *3 for RH

    1. for LH:


      1. Disconnect the A22 front fog light connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        A22-2 - Body ground Light control switch TAIL, front fog light switch on 11 to 14 V
        Light control switch TAIL, front fog light switch off Below 1 V

    2. for RH:


      1. Disconnect the A18 front fog light connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        A18-2 - Body ground Light control switch TAIL, front fog light switch on 11 to 14 V
        Light control switch TAIL, front fog light switch off Below 1 V

    NG

    INSPECT FRONT FOG LIGHT RELAY FRONT (FR FOG) Click here

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT FOG LIGHT BULB - BODY GROUND)

  3. INSPECT FRONT FOG LIGHT RELAY FRONT (FR FOG)

    A003C41E08

    1. Remove the FR FOG relay from the No. 2 relay block.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage not applied to terminals 1 and 2 10 kΩ or higher
      Battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG

    REPLACE FR FOG RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (FR FOG RELAY - BATTERY AND TAIL RELAY)

    A003CVWE01
    Text in Illustration
    *1

    Component without relay connected

    (No. 2 Relay Block)
    *2

    Component without harness connected

    (Center Airbag Sensor)

    1. Remove the FR FOG relay from the No. 2 relay block.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      FR FOG relay terminal 2 - Body ground Light control switch TAIL 11 to 14 V
      FR FOG relay terminal 5 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (FR FOG RELAY - FRONT FOG LIGHT BULB)


    1. A003AQNE01
      Text in Illustration
      *1

      Component without relay connected

      (No. 2 Relay Block)
      *2

      Front view of wire harness connector

      (to Front Fog Light Bulb)
      *3 for LH
      *4 for RH

      Remove the FR FOG relay from the No. 2 relay block.

    2. for LH:


      1. Disconnect the A22 front fog light connector.

      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        FR FOG relay terminal 3 - A22-2 Always Below 1 Ω
        FR FOG relay terminal 3 - Body ground Always 10 kΩ or higher

    3. for RH:


      1. Disconnect the A18 front fog light connector.

      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        FR FOG relay terminal 3 - A18-2 Always Below 1 Ω
        FR FOG relay terminal 3 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (FR FOG RELAY - MAIN BODY ECU)

    A003DMNE01
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Main Body ECU)

    1. Disconnect the D81 main body ECU connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      D81-17 (FFGO) - Body ground Light control switch TAIL 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU