LIGHTING SYSTEM Rear Fog Light Circuit

DESCRIPTION

Illumination of the rear fog lights is controlled by the main body ECU (multiplex network body ECU).

WIRING DIAGRAM

B005AWLE03

CAUTION / NOTICE / HINT

Note


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

  • Before performing troubleshooting, check that the taillight relay circuit operates properly.

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

  • 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.*

    *: w/ Door Control Battery

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (REAR FOG LIGHT RELAY)


    1. Using the GTS, perform the Active Test.

      Click here


      Body Electrical > Main Body > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Rear Fog Light Relay Rear fog light relay ON or OFF The Headlight dimmer switch (fog switch) is in the tail position.

      Body Electrical > Main Body > Active Test
      Tester Display
      Rear Fog Light Relay

      Tech Tips

      Check the operation with the taillights illuminated.

      Result
      Result Proceed to
      The Active Test is performed normally A
      The Active Test is not performed normally (for LHD) B
      The Active Test is not performed normally (for RHD) C

    A
    C
    B
  2. INSPECT REAR FOG LIGHT RELAY (FOG RR)


    1. Remove the rear fog light relay from the junction block.

    2. Inspect the rear fog light relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - BATTERY)


    1. B0059H3C10
      *a

      Front view of wire harness connector

      (to Rear Fog Light Relay [FOG RR])

      Remove the rear fog light relay from the junction block.

    2. 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
    OK
  4. CHECK HARNESS AND CONNECTOR (TAIL RELAY - REAR FOG LIGHT RELAY [FOG RR])


    1. B0059H3C10
      *a

      Front view of wire harness connector

      (to Rear Fog Light Relay [FOG RR])

      Remove the rear fog light relay from the junction block.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Relay terminal 1 - Body ground
      • Headlight dimmer switch (fog switch) off →TAIL or HEAD (When vehicle has the dimmer switch off position)

      • Headlight dimmer switch (fog switch) in AUTO with low beams off → low beams on

      Below 1 V → 11 to 14 V
      If the low beams are illuminated, shine a light on the automatic light control sensor to change the system to daytime mode.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. CHECK HARNESS AND CONNECTOR (REAR LIGHT ASSEMBLY LH - REAR FOG LIGHT RELAY [FOG RR] AND BODY GROUND)


    1. Remove the rear fog light relay from the junction block.

    2. Disconnect the Y11 rear light assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - Y11-1 (B) Always Below 1 Ω
      Y11-4 (E) - Body ground Always Below 1 Ω
      Relay terminal 3 or Y11-1 (B) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])


    1. Remove the rear fog light relay from the junction block.

    2. Remove the instrument panel junction block assembly.

      Click here

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

      Click here

    4. Reconnect the instrument panel junction block assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 2 - A-27 (RFGO) Always Below 1 Ω
      Relay terminal 2 or A-27 (RFGO) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  7. INSPECT REAR LIGHT ASSEMBLY LH


    1. Remove the rear light assembly LH.

      Click here

    2. Inspect the rear light assembly LH.

      Click here

      Result
      Proceed to
      OK
      NG

    OK
    NG
  8. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the rear fog light relay from the junction block.

    2. Disconnect the 4C 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
      Relay terminal 1 - 4C-22 Always Below 1 Ω
      Relay terminal 1 or 4C-22 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK
    NG
  9. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the rear fog light relay from the junction block.

    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
      Relay terminal 2 - 4D-53 Always Below 1 Ω
      Relay terminal 2 or 4D-53 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK
    NG
  10. INSPECT REAR FOG LIGHT RELAY (FOG RR)


    1. Remove the rear fog light relay from the junction block.

    2. Inspect the rear fog light relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG
    OK
  11. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - BATTERY)


    1. B0059H3C10
      *a

      Front view of wire harness connector

      (to Rear Fog Light Relay [FOG RR])

      Remove the rear fog light relay from the junction block.

    2. 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
    OK
  12. CHECK HARNESS AND CONNECTOR (TAILLIGHT RELAY [TAIL RELAY] - REAR FOG LIGHT RELAY [FOG RR])


    1. B0059H3C10
      *a

      Front view of wire harness connector

      (to Rear Fog Light Relay [FOG RR])

      Remove the rear fog light relay from the junction block.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Relay terminal 1 - Body ground
      • Headlight dimmer switch (fog switch) off →TAIL or HEAD (When vehicle has the dimmer switch off position)

      • Headlight dimmer switch (fog switch) in AUTO with low beams off → low beams on

      Below 1 V → 11 to 14 V
      If the low beams are illuminated, shine a light on the automatic light control sensor to change the system to daytime mode.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  13. CHECK HARNESS AND CONNECTOR (REAR LIGHT ASSEMBLY RH - REAR FOG LIGHT RELAY [FOG RR] AND BODY GROUND)


    1. Remove the rear fog light relay from the junction block.

    2. Disconnect the Y10 rear light assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - Y10-1 (B) Always Below 1 Ω
      Y10-4 (E) - Body ground Always Below 1 Ω
      Relay terminal 3 or Y10-1 (B) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  14. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])


    1. Remove the rear fog light relay from the junction block.

    2. Remove the instrument panel junction block assembly.

      Click here

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

      Click here

    4. Reconnect the instrument panel junction block assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 2 - A-27 (RFGO) Always Below 1 Ω
      Relay terminal 2 or A-27 (RFGO) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  15. INSPECT REAR LIGHT ASSEMBLY RH


    1. Remove the rear light assembly RH.

      Click here

    2. Inspect the rear light assembly RH.

      Click here

      Result
      Proceed to
      OK
      NG

    OK
    NG
  16. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the rear fog light relay from the junction block.

    2. Disconnect the 4C 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
      Relay terminal 1 - 4C-22 Always Below 1 Ω
      Relay terminal 1 or 4C-22 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK
    NG
  17. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the rear fog light relay from the junction block.

    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
      Relay terminal 2 - 4D-53 Always Below 1 Ω
      Relay terminal 2 or 4D-53 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK
    NG