Inspection Procedure 1: The Front Fog Lamps do not Illuminate Normally.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.


COMMENTS ON TROUBLE SYMPTOM
If the front fog lamps do not illuminate normally, the input signal circuit(s) below or the ETACS-ECU may be defective.

  • Tail lamp switch
  • Headlamp switch
  • Front fog lamp switch

PROBABLE CAUSES

  • Malfunction of the column switch
  • Malfunction of the front fog lamp relay
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Check that the tail/stop lamps and headlamps operate.
Check that the tail/stop lamps and headlamps illuminate normally.

Q. Is the check result normal?
Go to Step 2.
Repair the tail/stop lamp(s) and headlamp(s). Refer to trouble symptom chart .

STEP 2. M.U.T.-III diagnosis code.
When the ignition switch is turned to the "LOCK" (OFF) position, check that the ETACS-ECU does not set the diagnosis code.

Q. Is the diagnosis code set?
Refer to diagnosis code chart .
Go to Step 3.

STEP 3. M.U.T.-III data list
Check the input signals below, which are related to the front fog lamp.

  • Turn the ignition switch to the "LOCK" (OFF) position.
  • Turn the tail lamp switch to the ON position.
  • Turn the front fog lamp switch to the ON position.
Item No.
 Item name
 Normal condition
30
 Ignition switch(IG1)
 OFF
70
 Front fog lamp
 ON
OK: Normal conditions are displayed for all the items

Q. Are the check result normal?
YES <All the signals are received normally.> : Go to Step 4.
NO <The ignition switch (IG1) signal is not received.> : Refer to inspection procedure C-3 "The ignition switch (IG1) signal is not received ."
NO <The front fog lamp switch signal is not received.> : Refer to inspection procedure C-1 "The column switch (lighting and wiper switch) signal is not received ."

STEP 4. Connector check: A-13X front fog lamp relay connector

Q. Is the check result normal?

Go to Step 5.

Repair the defective connector.

STEP 5. Check the front fog lamp relay.
Refer to .

Q. Is the check result normal?
Go to Step 6.
Replace the front fog lamp relay.

STEP 6. Voltage measurement at the A-13X front fog lamp relay connector.

(1)Remove the front fog lamp relay, and measure at the relay box side.

(2)Check the voltage between the front fog lamp relay connector and body earth.

  • Voltage between A-13X front fog lamp relay connector terminal No.1 and body earth
  • Voltage between A-13X front fog lamp relay connector terminal No.4 and body earth
OK: System voltage

Q. Is the check result normal?

Go to Step 8.

Go to Step 7.

STEP 7. Check the wiring harness between A-13X front fog lamp relay connector terminals Nos.1 and 4 to the fusible link (23).


  • Check the power supply line for open circuit.

Q. Is the check result normal?

Go to Step 10.

Repair the wiring harness.

STEP 8. Connector check: C-219 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 9.

Repair the defective connector.

STEP 9. Check the wiring harness between A-13X front fog lamp relay connector terminal No.2 to C-219 ETACS-ECU connector terminal No.67.





note Prior to the wiring harness inspection, check intermediate connector C-33, and repair if necessary.

  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 10.

Repair the wiring harness.

STEP 10. Retest the system
Check that the front fog lamps illuminate normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.