Inspection Procedure A-1: When the Ignition Switch is at the "LOCK" (OFF) Position, the Functions do not Work Normally. Check the Battery Power Supply Circuit to the ETACS-ECU.

caution

Whenever the ECU is replaced, ensure that the power supply circuit and the earthing circuit are normal.

COMMENTS ON TROUBLE SYMPTOM

If this circuit is defective and the ignition switch is at the "LOCK" (OFF) position, the ETACS-ECU does not work. In this case, the functions below will be suspended.

Lamp reminder function
Keyless entry system

However, when the ignition switch is at the ON position, the functions below will work.

Reading diagnosis code and checking input signal by M.U.T.-III.
Central door locking
Headlamp and tail lamp
Hazard warning lamp
Room lamps

PROBABLE CAUSES

Malfunction of the ETACS-ECU
Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Check the power supply voltage of the ETACS-ECU.

Turn the ignition switch to the "LOCK" (OFF) position

Item No.	Item name	Normal condition
55	Battery voltage(battery)	System voltage

OK: Normal condition is displayed.

Q. Is the check result normal?

	Go to Step 4.

	Go to Step 2.

STEP 2. Connector check: C-218 ETACS-ECU connector

Q. Is the check result normal?

Go to Step 3.

Repair the defective connector.

STEP 3. Check the wiring harness between C-218 ETACS-ECU connector terminal No.20 and fusible link (20).

note

Prior to the wiring harness inspection, check junction block connector C-213, and repair if necessary.

Check the power supply line for open circuit.

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

Repair the wiring harness.

STEP 4. Resistance measurement at the C-218 ETACS-ECU connector.

(1)Remove the ETACS-ECU, and measure at the junction block side.

(2)Continuity between C-218 ETACS-ECU connector terminal No.2 and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 6.

Go to Step 5.

STEP 5. Check the wiring harness between C-218 ETACS-ECU connector terminal No.2 and body earth.

note

Prior to the wiring harness inspection, check junction block connector C-208, 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 use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction

Repair the wiring harness.

STEP 6. Retest the system.

Check that the battery power supply circuit to the ETACS-ECU is normal.

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.