Inspection Procedure 1: The front room lamp does not illuminate normally.


caution Whenever the ECU is replaced, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.

OPERATION


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

COMMENTS ON TROUBLE SYMPTOM


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

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Retest the system.


Q. At which switch positions (DOOR or ON), the front room lamp does not illuminate?

The lamp does not illuminate at both the DOOR and ON positions. : Go to Step 2.

The lamp does not illuminate at the ON position. : Go to Step 4.

The lamp does not illuminate at the DOOR position. : Go to Step 6.

STEP 2. Front room lamp bulb check


Check that the front room lamp bulb is normal.

Q. Is the check result normal?

Go to Step 3.

Replace the front room lamp bulb (Refer to ).

STEP 3. Check of open circuit in power supply lines between the front room lamp connector and the fusible link.


Q. Is the check result normal?

Go to Step 5.

Repair the connector(s) or wiring harness.

STEP 4. Check of open circuit in earth line between the front room lamp connector and the body earth.


Q. Is the check result normal?

Go to Step 5.

Repair the connector(s) or wiring harness.

STEP 5. Retest the system


Check that the front 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 room lamp assembly (Refer to ).

STEP 6. M.U.T.-III data list


Use the ETACS-ECU service data to check the signals related to the operation of front room lamp.

Item No.
 Item name
 Normal condition
19
 Driver’s door switch
 ON
20
 Driver’s door unlock switch
 ON
28
 Steering lock switch
 OFF → ON
30
 IG SW (IG1)
 OFF
48
 Passenger’s door switch
 ON
49
 Rear door switch
 ON
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?

Normal conditions are displayed for all the items. : Go to Step 7.

Normal condition is not displayed for item No. 19. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 5 "The front door switch (driver’s side) signal is not received" .

Normal condition is not displayed for item No. 20. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 4 "The front door lock actuator (driver’s side) signal is not received" .

Normal condition is not displayed for item No. 28. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 3 "Key reminder switch signal is not received" .

Normal condition is not displayed for item No. 30. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 2 "The ignition switch (IG1) signal is not received" .

Normal condition is not displayed for item No. 48. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 6 "The front door switch (passenger’s side) signal is not received ."

Normal condition is not displayed for item No. 49. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 7 "One of the door switch signals is not received ."

STEP 7. Check of open circuit in ROOM LP lines between the front room lamp connector and the ETACS-ECU connector.


Q. Is the check result normal?

Go to Step 8.

Repair the connector(s) or wiring harness.

STEP 8. Retest the system


Check that the front 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 (Refer to ETACS-ECU ).