Inspection Procedure C-1

Central Door Locking System: Central Door Locking System Does Not Operate

Door Lock Actuator Circuit:

Connectors:

CIRCUIT OPERATION
- The ETACS-ECU operates the door lock actuators through its dedicated relay (integrated in the ETACS-ECU).
- The ETACS-ECU drives the relay to lock or unlock the door if the requirements are satisfied.

TECHNICAL DESCRIPTION (COMMENT)
The power supply circuit, the circuit shared by door lock actuators, or the ETACS-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tool:
- MB991223: Harness Set




STEP 1. Check the ETACS-ECU power supply circuit [fusible link (2)] at the ETACS-ECU connector C-114.
1. Disconnect the ETACS-ECU connector C-114 and measure at the junction block side.
2. Measure the voltage between terminal 16 and ground.

Q: Is the voltage approximately 12 volts (battery positive voltage)?

YES: Go to Step 4.

NO: Go to Step 2.




STEP 2. Check the junction block connector C-114 for damage.

Q: Is junction block connector C-114 in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Refer to Harness Connector Inspection. The central door locking system should work normally.













STEP 3. Check the harness wires between ETACS-ECU connector C-114 end fusible link (2).

NOTE: After checking junction block connector C-110 and intermediate connector C-89, check the wires. If junction block connector C-110 and intermediate connector C-89 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the harness wires between ETACS-ECU connector C-114 and fusible link (2) in good condition?

YES: There is no action to be taken.

NO: Repair them. The central door locking system should work normally.




STEP 4. Check the junction black connector C-114 for damage

Q: Is junction block connector C-114 in good condition?

YES: Go to Step 5.

NO: Repair or replace it. Refer to Harness Connector Inspection. The central door locking system should work normally.










STEP 5. Check the harness wires between ETACS-ECU connector C-114 and driver's door lock actuator connector E-13.






NOTE: After checking intermediate connector C-91 and junction block connector C-104 and C-107, check the wires. If intermediate connector C-91 and junction block connector C-104 and C-107 are damaged, repair or replace it. Refer to Harness Connector Inspection.

Q: Are the harness wires between ETACS-ECU connector C-114 and intermediate connector C-91 in good condition?

YES: Replace the ETACS-ECU. The central door locking system should work normally.

NO: Repair them. The central door locking system should work normally.