INSPECTION PROCEDURE P-3: The fog lamp switch signal is not received.


caution Whenever the ECU is replaced, ensure that the input signal circuit is normal.


COMMENTS ON TROUBLE SYMPTOM
Input signal from the fog lamp switch is used to operate the fog lamps. If the signal is abnormal, the fog lamps will not illuminate and extinguish normally.

POSSIBLE CAUSES

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

DIAGNOSIS PROCEDURE

Step 1. Connector check: C-130 fog lamp switch connector

Q. Is the check result normal?

Go to Step 2.

Repair the defective connector.

Step 2. Check the front fog lamp switch.
Refer to GROUP 54A - Fog lamp .

Q. Is the check result normal?
Go to Step 3.
Replace the fog lamp switch.

Step 3. Resistance measurement at the C-130 fog lamp switch connector.

(1)Remove the fog lamp switch, and measure at the wiring harness side.

(2)Resistance between C-130 fog lamp switch connector terminal No.2 and body earth
OK: 2Ω or less

Q. Is the check result normal?

Go to Step 5.

Go to Step 4.

Step 4. Check the wiring harness from C-130 fog lamp switch connector terminal No.2 to body earth.


note Prior to the wiring harness inspection, check joint connector C-01, and repair if necessary.

  • Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

Repair the wiring harness.

Step 5. Connector check: C-221 ETACS-ECU connector

Q. Is the check result normal?

Go to Step 6.

Repair the defective connector.

Step 6. Check the wiring harness from C-221 ETACS-ECU connector No.54 to C-130 fog lamp switch connector terminal No.1.



  • Check the input line for open circuit.

Q. Is the check result normal?

Go to Step 7.

Repair the wiring harness.

Step 7. SWS monitor data list
<Selected item> ETACS ECU
  • Ignition switch: ON
  • Lighting switch: "TAIL" or "HEAD"
  • Fog lamp switch: OFF → ON
Item No.
 Item name
 Normal condition
Item 36
 F.FOG LAMP
 OFF → ON
OK: Normal condition is displayed.

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