Inspection Procedure 1: Central door locking system does not work at all.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.






OPERATION



COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of the front door lock actuator (driver’s side)
  • Malfunction of ETACS-ECU
  • Damaged wiring harness and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code
Check that ETACS-ECU sets a diagnosis code.

Q. Is the diagnosis code set?
Refer to GROUP 54A - Troubleshooting .
Go to Step 2.

STEP 2. M.U.T.-III data list
Check the signals related to the central door locking system operation.

  • Set the inside lock knob at the lock position.
Item No.
 Item name
 Normal condition
20
 Driver’s door unlock switch
 OFF
21
 Driver’s door lock switch
 ON

  • Set the inside lock knob at the unlock position.
Item No.
 Item name
 Normal condition
20
 Driver’s door unlock switch
 ON
21
 Driver’s door lock switch
 OFF
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?
Go to Step 3.
Refer to GROUP 54A - Inspection Procedure 4 "The front door lock actuator (driver’s side) signal is not received ".

STEP 3. Connector check: B-304 ETACS-ECU connector

Q. Is the check result normal?
Go to Step 4.
Repair the defective connector.

STEP 4. Check the wiring harness between B-304 ETACS-ECU connector terminal No.1 and fusible link (25).
note Prior to the wiring harness inspection, check junction block connector B-310 and repair if necessary.

  • Check the power supply line for open or short circuit.

Q. Is the check result normal?
Go to Step 5.
Repair the wiring harness.

STEP 5. Retest the system.
Check that the central door locking system works 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 and register the ID codes (Refer to GROUP 54A, Encrypted Code Registration Criteria Table ).