Inspection Procedure 1: The front 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




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

COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



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

DIAGNOSIS PROCEDURE


STEP 1. Rear room lamp operation check



Q. Is the check result normal?





STEP 2. M.U.T.-III diagnosis code



Q. Is the diagnosis code set?





STEP 3. M.U.T.-III data list




  • Turn the ignition switch to the LOCK (OFF) position.
  • Remove the ignition key from the ignition key cylinder.
  • Open each door.
Item No.
 Item name
 Normal condition
Item 228
 Dr door unlock
 ON
Item 254
 IG voltage
 1 V or less
Item 256
 Dr door ajar switch
 Open
Item 257
 As door ajar switch
 Open
Item 258
 RR door ajar switch
 Open
Item 259
 RL door ajar switch
 Open
Item 264
 Handle lock switch
 Key in → Key out
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?

















STEP 4. Front room lamp bulb check



Q. Is the check result normal?





STEP 5. Check of open circuit in (LP+1, LP+2, LP+3&LP+4) line between the front room lamp connector and ETACS-ECU connector.


Q. Is the check result normal?





STEP 6. Check of open circuit in (RLP-1, RLP-2&RLP-3) line between the front room lamp connector and ETACS-ECU connector.


Q. Is the check result normal?





STEP 7. Check of open circuit in earth line between the front room lamp connector and body earth.


Q. Is the check result normal?





STEP 8. Retest the system



Q. Is the check result normal?