DESCRIPTION
The main body ECU controls the rear fog relay when a signal is received from the headlight dimmer switch assembly.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
PERFORM ACTIVE TEST USING INTELLIGENT TESTER
Connect the intelligent tester to the DLC3.
Turn the ignition switch on (IG).
Turn the intelligent tester on.
Select the following menu items: Body Electrical / Main Body / Active Test.
Check that the relay operate.
| Tester Display | Test Part | Control Range | Diagnostic Note |
|---|---|---|---|
| Rear Fog Light Relay | Rear fog light relay | ON/OFF | - |
| OK |
|---|
| Rear fog light relay operates. (Rear fog light comes on.) |
| NG |
|
INSPECT FUSE (RR FOG) Click here |
| OK |
|
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here
INSPECT FUSE (RR FOG)
Remove the RR FOG fuse from the instrument panel junction block.
Measure the resistance according to the value(s) in the table below.
| Standard resistance | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPLACE FUSE |
| OK |
|
INSPECT REAR FOG LIGHT RELAY (RR FOG)
Remove the rear fog light relay from the engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPLACE REAR FOG LIGHT RELAY |
| OK |
|
CHECK HARNESS AND CONNECTOR (BATTERY - REAR FOG LIGHT RELAY)
Measure the voltage according to the value(s) in the table below.
| Standard voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY - MAIN BODY ECU)
Disconnect the D8 main body ECU connector.
Measure the resistance according to the value(s) in the table below.
| Standard resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK)
Reconnect the D8 main body ECU connector.
Install the rear fog light relay to the engine room relay block.
Measure the voltage according to the value(s) in the table below.
| Standard voltage | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK) |
| OK |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (REAR FOG LIGHT RELAY - BODY GROUND)