Inspection Procedure C-19: The interior lamp "all on" or "all off" switch signal is not sent to the ETACS-ECU.


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














COMMENTS ON TROUBLE SYMPTOM
Input signals from the interior lamp "ON" and "OFF" switch are used to operate the interior lamps (interior lamp, rear personal lamp, luggage compartment lamp, door lamps and key illumination lamp). If the signals are abnormal, the interior lamps will not illuminate and extinguish normally.

PROBABLE CAUSES

  • Malfunction of the front room lamp (interior lamp switch)
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: E-102 front room lamp connector

Q. Is the check result normal?
Go to Step 2.
Repair the connector.

STEP 2. Check the front room lamp.
Refer to .

Q. Is the check result normal?
Go to Step 3.
Replace the front room lamp.

STEP 3. Resistance measurement at E-102 front room lamp connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Resistance between E-102 front room lamp connector terminal No.5 and body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 5.
Go to Step 4.

STEP 4. Check the wiring harness between E-102 front room lamp connector terminal No.5 and body earth

  • 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: D-420 ETACS-ECU connector

Q. Is the check result normal?
Go to Step 6.
Repair the defective connector.

STEP 6. Check the wiring harness between E-102 front room lamp connector terminal Nos.6, 7 and D-420 ETACS-ECU connector terminal Nos.53, 63.
note Prior to the wiring harness inspection, check intermediate connector D-130, and repair if necessary.

  • Check the input line for open and short circuit.

Q. Is the check result normal?
Go to Step 7.
Repair the wiring harness.

STEP 7. Retest the system.
Check that the front room lamp signal is received normally.

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.