LIGHTING SYSTEM Rear Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the rear fog light.

WIRING DIAGRAM

B003YMLE04

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses and bulb 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
      Rear Fog Light Relay Rear fog light relay ON/OFF Light control switch in tail position

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

    OK

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

    NG

  3. CHECK HARNESS AND CONNECTOR (REAR LIGHT ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND BODY GROUND)


    1. for LHD:


      1. Disconnect the Q44 rear light assembly LH connector.

      2. Disconnect the 4D instrument panel junction block assembly connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q44-4 (B) - 4D-12 Always Below 1 Ω
        Q44-4 (B) - Body ground Always 10 kΩ or higher
        Q44-3 (E) - Body ground Always Below 1 Ω

    2. for RHD:


      1. Disconnect the Q6 rear light assembly RH connector.

      2. Disconnect the 4D instrument panel junction block assembly connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q6-4 (B) - 4D-12 Always Below 1 Ω
        Q6-4 (B) - Body ground Always 10 kΩ or higher
        Q6-3 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. 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.

      B003YJ1C01
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    3. Connect a positive (+) lead from the auxiliary battery to terminal 4E-1.

    4. Connect a negative (-) lead from the auxiliary battery to terminal MB-14 (TRLY) and MB-27 (RFGO).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      4D-12 - Auxiliary battery negative (-) terminal Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here