Inspection Procedure 2: The rear room lamp does not illuminate normally.

caution

Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in Immobilizer System - How to Register Key ID .)

OPERATION

The ETACS-ECU illuminates and extinguishes the rear room lamp in accordance with the input signals below.

Ignition switch (IG1)
Key reminder switch
Door switches
Front door lock actuator (driver’s side)

COMMENTS ON TROUBLE SYMPTOM

If this does not work normally, the above switch input circuit(s), rear room lamp, or ETACS-ECU may have a problem.

PROBABLE CAUSES

Malfunction of the key reminder switch
Malfunction of door switch
Malfunction of the front door lock actuator (driver’s side)
Malfunction of rear room lamp
Malfunction of the ETACS-ECU
Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Front room lamp operation check

Check that the front room lamp illuminates and extinguishes normally.

Q. Is the check result normal?

Go to Step 2.

Refer to Inspection Procedure 1 "The front room lamp does not illuminate normally."

STEP 2. Rear room lamp bulb check

Check that the rear room lamp bulb is normal.

Q. Is the check result normal?

Go to Step 3.

Replace the rear room lamp bulb.

STEP 3. Check of open circuit in (LP+1, LP+2, LP+3&LP+4) line between the rear room lamp connector and ETACS-ECU connector.

Q. Is the check result normal?

Go to Step 4.

Repair the connector(s) or wiring harness.

STEP 4. Check of open circuit in (RLP-1, RLP-2&RLP-3) line between the rear room lamp connector and ETACS-ECU connector.

Q. Is the check result normal?

Go to Step 5.

Repair the connector(s) or wiring harness.

STEP 5. Check of open circuit in earth line between the rear room lamp connector and body earth.

Q. Is the check result normal?

Replace the rear room lamp, and then go to Step 6.

Repair the connector(s) or wiring harness.

STEP 6. Retest the system

Check that the rear room lamp illuminates/extinguishes 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.