Front Fog Light Circuit

LIGHTING: LIGHTING SYSTEM: Front Fog Light Circuit

Front Fog Light Circuit

DESCRIPTION

The main body ECU receives a front fog light switch information signal from the light control switch (front fog switch), and illuminates the front fog lights.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (FRONT FOG LIGHT)
(a) Operate the Techstream according to the steps on the display and select "Active Test".

Main Body





OK:
Front fog light turns on / turns off.
NG -- INSPECT FUSE (FOG)
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
2. INSPECT FUSE (FOG)
(a) Remove the FOG fuse from the engine room junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (FRONT FOG LIGHT BULB - BATTERY)




(a) for LH:
(1) Disconnect the A30 front fog light connector.
(2) Measure the voltage according to the value(s) in the table below.
Standard voltage:









(b) for RH:
(1) Disconnect the A31 front fog light connector.
(2) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- INSPECT FOG LIGHT RELAY (FR FOG)
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT FOG LIGHT BULB - BODY GROUND)
4. INSPECT FOG LIGHT RELAY (FR FOG)




(a) Remove the fog light relay from the engine room relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE FOG LIGHT RELAY
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (FOG LIGHT RELAY - BATTERY)




(a) Remove the fog light relay from the engine room relay block.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (FR FOG RELAY - FRONT FOG LIGHT BULB)




(a) Remove the fog light relay from the engine room relay block.
(b) for LH:
(1) Disconnect the A30 front fog light connector.
(2) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(c) for RH:
(1) Disconnect the A31 front fog light connector.
(2) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
7. CHECK FRONT FOG LIGHT




(a) Disconnect the J4 ECU connector.
(b) Using a service wire, connect J4-4 (FFGO) on the wire harness side and body ground.
(c) Check that the front fog light illuminates.
OK:
Front fog light illuminates.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FOG LIGHT RELAY - MAIN BODY ECU)
OK -- REPLACE MAIN BODY ECU