LIGHTING SYSTEM Rear Fog Light Circuit

DESCRIPTION

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

WIRING DIAGRAM

A002CAUE03

CAUTION / NOTICE / HINT

Note


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

  • If the main body ECU (multiplex network body ECU) is replaced, refer to Service Bulletin.*


    • *: w/ Smart Entry and Start System

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.*

    Click here


    • *: for LHD

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 ignition switch to ON.

    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 lights come on.)
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  3. INSPECT RR FOG LP RELAY


    1. A002B70C37
      *a

      Component without harness connected

      (RR FOG LP Relay)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Voltage not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 Voltage applied between terminals 1 and 2 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE RR FOG LP RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (RR FOG LP RELAY INPUT VOLTAGE)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (RR FOG LP RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Disconnect the 4H 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
      Relay terminal 1 - 4H-26 Always Below 1 Ω
      Relay terminal 2 - 4H-16 Always Below 1 Ω
      Relay terminal 1 - Body ground Always 10 kΩ or higher
      Relay terminal 2 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (RR FOG LP RELAY - REAR FOG LIGHT ASSEMBLY)


    1. for LH Side:


      1. Disconnect the W6 rear light assembly LH connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Relay terminal 3 - W6-1 Always Below 1 Ω
        Relay terminal 3 - Body ground Always 10 kΩ or higher

    2. for RH Side:


      1. Disconnect the W5 rear light assembly RH connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Relay terminal 3 - W5-1 Always Below 1 Ω
        Relay terminal 3 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. 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.

      A002CLMC03
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

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

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

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      4H-16 - Battery negative (-) terminal Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  8. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


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

      A002C7KC01
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      4H-26 - MB-27 (RFGO) Always Below 1 Ω
      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