Inspection Procedure C-1

Connectors:

INSPECTION PROCEDURE C-1: Central Door Locking System: Central door locking system does not operate.

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
- The ETACS-ECU may be defective.
- The wiring harness or connectors may have loose, corroded or damaged terminals, or terminals pushed back in the connector.

DIAGNOSIS
Required Special Tool:
- MB991223: Harness Set

STEP 1. Check the battery power supply circuit to the ETACS-ECU. Test at ETACS-ECU connector C-319.




1. Disconnect ETACS-ECU connector C-319 and measure the voltage available at the junction block side of the connector.




2. Measure the voltage between terminal 2 and ground.
- The voltage should measure approximately 12 volts (battery positive voltage).

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

YES : Go to Step 4.

NO : Go to Step 2.




STEP 2. Check ETACS-ECU connector C-319 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connector C-319 in good condition?

YES : Go to Step 3.

NO : Repair or replace the damaged components). Refer to Harness Connector Inspection. Verify that the central door locking system works normally.







STEP 3. Check the wiring harness between ETACS-ECU connector C-319 (terminal 2) and the fusible link (1).

NOTE: Also check intermediate connector C-209 and junction block connector C-313 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-209 or junction block connector C-313 is damaged, repair or replace the damaged components) as described in Harness Connector Inspection.







Q: Is the wiring harness between ETACS-ECU connector C-319 (terminal 2) and fusible link (1) in good condition?

YES : No action is necessary and testing is complete.

NO : The wiring harness may be damaged or the connector may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the central door locking system works normally.







STEP 4. Check ETACS-ECU connector C-317 and C-319 and driver's door lock actuator connector E-13 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connector C-317 and C-319 and driver's door lock actuator connector E-13 in good condition?

YES : Go to Step 5.

NO : The Wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair or replace the damaged component(s). Refer to Harness Connector Inspection. Verify that the central door locking system works normally.













STEP 5. Check the wiring harness between ETACS-ECU connector C-317 (terminal 22) and C-319 (terminal 12) and driver's door lock actuator
connector E-13 (terminals 4 and 6).

NOTE: Also check intermediate connector C-211 and junction block connector C-308 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-211 or junction block connector C-308 is damaged, repair or replace the damaged components) as described in Harness Connector Inspection?.

Q: Is the wiring harness from ETACS-ECU connectors C-317 (terminal 22) and C-319 (terminal 12) to driver's door lock actuator connector E-13 (terminals 4 and 6) in good condition?

YES : Replace the ETACS-ECU. Verify that the central door locking system works normally.

NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair or replace the damaged component(s). Verify that the central door locking system works normally.