LIGHTING SYSTEM Front Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the front fog lights.

WIRING DIAGRAM

A01CZTSE04

CAUTION / NOTICE / HINT

Note


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

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.

PROCEDURE


  1. CHECK OPERATION (TAILLIGHTS)


    1. Check the operation of the taillights.

      OK
      Taillights operate normally.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO PROBLEM SYMPTOMS TABLE Click here

    OK

  2. PERFORM ACTIVE TEST USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Active Test.

    5. Check that the relay operates.


      Body Electrical > Main Body > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Front Fog Light Relay Front fog light relay ON/OFF Light control switch in tail position

      Body Electrical > Main Body > Active Test
      Tester Display
      Front Fog Light Relay
      OK
      Front fog light relay operates. (Front fog lights come on.)
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  3. CHECK SEMICONDUCTOR PWR INTEGRATION ECU


    1. Using a voltmeter, check the signal reading of the semiconductor pwr integration ECU.

      Click here

      OK
      Output signal reading is normal.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT SEMICONDUCTOR PWR INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU POWER SOURCE AND BODY GROUND)


    1. Remove the semiconductor pwr integration ECU from the No. 1 engine room relay block and No. 1 junction block assembly.

      Click here

      A01D04UC01
      *a

      Component without semiconductor pwr integration ECU connected

      (No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly)

      		 - -

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1B-1 (BATT) - Body ground Power switch off 11 to 14 V
      1A-1 (ALT) - Body ground Power switch off 11 to 14 V
      1E-4 (TAIL) - Body ground Power switch off, headlight dimmer switch in tail position 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1D-14 (GND1) - Body ground Always Below 1 Ω
      1G-5 (GND2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Disconnect the 4C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1D-7 (FOGS) - 4C-27 Always Below 1 Ω
      1D-7 (FOGS) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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

      B003Y2XC03
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      4C-27 - MB-7 (FFGO) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - FOG LIGHT ASSEMBLY LH AND FOG LIGHT ASSEMBLY RH)


    1. Disconnect the A36 fog light assembly LH connector.

    2. Disconnect the A4 fog light assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1E-7 (L) - A36-2 Always Below 1 Ω
      1E-7 (L) - A4-2 Always Below 1 Ω
      1E-7 (L) - Body ground Always 10 kΩ or higher
      A36-1 - Body ground Always Below 1 Ω
      A4-1 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK SEMICONDUCTOR PWR INTEGRATION ECU


    1. Replace the semiconductor pwr integration ECU with a new or known good one.

      Click here

    2. Check that the front fog lights operate normally.

      OK
      The front fog lights operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (SEMICONDUCTOR PWR INTEGRATION ECU WAS DEFECTIVE)

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here