Step 1. Check that the tail lamps and headlamps operate.

Check that the tail lamps and headlamps illuminate normally.

Q: Is the check result normal?

YES:  Go to Step 2.
NO:  Check the tail lamps and the headlamps (Refer to trouble symptom chart ).

Step 2. Pulse check

Check the input signals below, which are related to the rear fog lamps.

System switch	Check condition
Ignition switch (IG1)	When turned from ACC to ON
Tail lamp switch	When the lighting switch is turned to the TAIL position
Headlamp switch	When the lighting switch is turned to the HEADLAMP position
Rear fog lamp switch	When the rear fog lamp switch is turned from off to on

OK: The MUT-II/III sounds or the voltmeter needle fluctuates.

Q: Is the check result normal?

All the signals are received normally.:  Go to Step 3.
The ignition switch (IG1) signal is not received.:  Refer to Inspection Procedure P-2 "The ignition switch (IG1) signal is not received ."
The tail lamp switch signal is not received.:  Refer to Inspection Procedure P-5 "The column switch (lighting and turn-signal lamp switch) signal is not received ."
The headlamp switch signal is not received.:  Refer to Inspection Procedure P-5 "The column switch (lighting and turn-signal lamp switch) signal is not received ."
The rear fog lamp switch signal is not received.:  Refer to Inspection Procedure P-17 "The rear fog lamp switch signal is not received ."

Step 3. Connector check: C-212 rear fog lamp relay connector

Q: Is the check result normal?

YES:  Go to Step 4.
NO:  Repair the defective connector.

Step 4. Check the rear fog lamp relay.

Refer to GROUP 54A - Rear fog lamp .
YES:  Go to Step 5.
NO:  Replace the rear fog lamp relay.

Step 5. Measure the voltage at the C-212 rear fog lamp relay connector.

1. Remove the rear fog lamp relay, and measure at the relay box side.

2. Check the voltage between the rear fog lamp relay connector and body earth.
• Voltage between C-212 rear fog lamp relay connector terminal No.3 and body earth
• Voltage between C-212 rear fog lamp relay connector terminal No.4 and body earth
OK: Battery positive voltage

Q: Is the check result normal?

YES:  Go to Step 7.
NO:  Go to Step 6.

Step 6. Check the wiring harness between C-212 rear fog lamp relay connector (terminal Nos.3 and 4) and the battery.

NOTE: Prior to the wiring harness inspection, check intermediate connector C-116 and junction block connectors C-201, C-204 and C-205, and repair if necessary.

• Check the power supply line for open circuit.

Q: Is the check result normal?

YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.

Step 7. Connector check: C-219 ETACS-ECU connector

Q: Is the check result normal?

YES:  Go to Step 8.
NO:  Repair the defective connector.

Step 8. Check the wiring harness between C-212 rear fog lamp relay connector terminal No.2 and C-219 ETACS-ECU connector terminal No.74.

NOTE: Prior to the wiring harness inspection, check junction block connector C-201, and repair if necessary.

• Check the output lines for open circuit.

Q: Is the check result normal?

YES:  Go to Step 9.
NO:  Repair the wiring harness.

Step 9. Retest the system.

Check that the rear fog lamps illuminate normally.

Q: Is the check result normal?

YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Replace the ETACS-ECU.