Lighting System Rear Fog Light Circuit

Body Electrical. Lexus Gs430, Gs300. Uzs190 Grs190
Lighting. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST BY INTELLIGENT TESTER

INSPECT FUSE (RR FOG)

REPLACE REAR LIGHT BULB (REAR FOG LH OR REAR FOG RH)

CHECK WIRE HARNESS (NO. 1 JUNCTION BLOCK - BATTERY)

CHECK WIRE HARNESS (NO. 1 JUNCTION BLOCK - REAR COMBINATION LIGHT (REAR FOG LH OR REAR FOG RH) - BODY GROUND)

LIGHTING SYSTEM - Rear Fog Light Circuit


DESCRIPTION

The multiplex network rear ECU receives rear fog light switch information from the combination switch, and turns on the rear fog lights.

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System.Lighting System Rear Fog Light Circuit


INSPECTION PROCEDURE

1.PERFORM ACTIVE TEST BY INTELLIGENT TESTER

  1. Select the item below in the Active Test, use the intelligent tester to generate a control command, and then check that the rear fog light illuminates.

    Multiplex network rear ECU:

    Item
    		Test Details
    		Diagnostic Note
    Rear fog light
    		Rear fog light ON / OFF
    		-
    OK:
    Rear fog light illuminates.


NG
Go to step 2
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2.INSPECT FUSE (RR FOG)

  1. Remove the RR FOG fuse from the No. 1 junction block.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


3.REPLACE REAR LIGHT BULB (REAR FOG LH OR REAR FOG RH)

  1. Temporarily replace the rear light bulb (rear fog LH or rear fog RH) with a new or normally functioning one.

  1. Check that the bulb illuminates.

    OK:
    Fog light bulb illuminates.


OK
END
NG


4.CHECK WIRE HARNESS (NO. 1 JUNCTION BLOCK - BATTERY)


    Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System.Lighting System Rear Fog Light Circuit

  1. Disconnect the LB junction block connector.

  1. Measure the voltage of the wire harness side connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    LB-1 (RFRL) - Body ground
    		10 to 14 V


OK
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


5.CHECK WIRE HARNESS (NO. 1 JUNCTION BLOCK - REAR COMBINATION LIGHT (REAR FOG LH OR REAR FOG RH) - BODY GROUND)


    Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System.Lighting System Rear Fog Light Circuit

  1. Check the wire harness between the rear combination light (rear fog LH) and No. 1 junction block, and the rear combination light (rear fog LH) and body ground.

    1. Disconnect the a2 light connector.

    2. Disconnect the LA junction block connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance:
      Tester Connection
      		Specified Condition
      LA-13 - a2-3 (B)
      		Below 1 Ω
      LA-13 or a2-3 (B) - Body ground
      		10 kΩ or higher

    4. Connect the LA junction block connector.

    5. Measure the resistance of the wire harness side connector.

      Standard resistance:
      Tester Connection
      		Specified Condition
      a2-4 (E) - Body ground
      		Below 1 Ω


    Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System.Lighting System Rear Fog Light Circuit

  1. Check the wire harness between the rear combination light (rear fog RH) and No. 1 junction block, and the rear combination light (rear fog RH) and body ground.

    1. Disconnect the a9 light connector.

    2. Disconnect the LA junction block connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance:
      Tester Connection
      		Specified Condition
      LA-13 - a9-3 (B)
      		Below 1 Ω
      LA-13 or a9-3 (B) - Body ground
      		10 kΩ or higher

    4. Connect the LA junction block connector.

    5. Measure the resistance of the wire harness side connector.

      Standard resistance:
      Tester Connection
      		Specified Condition
      a9-4 (E) - Body ground
      		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE