42A-CENTRAL DOOR LOCKING SYSTEM DOES NOT OPERATE

INSPECTION PROCEDURE A-1: Central door locking system does not work at all.

caution

Before replacing the ECU, ensure that the power supply circuit, the ground 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

The ETACS-ECU controls the central door locking system, locking or unlocking all the doors by activating the central door lock relay (built in the ETACS-ECU). The ETACS-ECU uses input signals from the door lock switch, which is incorporated in the power window main switch or power window sub switch.

COMMENTS ON TROUBLE SYMPTOM

If the central door locking system does not work at all, a malfunction of the door lock switch (built in the power window main switch or power window sub switch), front door lock actuator (driver's side) or ETACS-ECU is suspected.

TROUBLESHOOTING HINTS

Malfunction of the door lock switch (built in the power window main switch or power window sub switch)
Malfunction of the front door lock actuator (driver's side)
Malfunction of ETACS-ECU
Damaged wiring harness and connectors

DIAGNOSIS

STEP 1. Using scan tool (M.U.T.-IIISE), read the diagnostic trouble code.

(1)

caution

To prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "OFF" position before connecting or disconnecting scan tool (M.U.T.-IIISE).

Connect scan tool (M.U.T.-IIISE). Refer to GROUP 54A, ETACS, "How to connect the scan tool (M.U.T.-IIISE)

(2) Turn the ignition switch to ON.

(3) Check if an ETACS-related diagnostic trouble code is set.

(4) Turn the ignition switch to OFF.

Is the DTC set?

Refer to GROUP 54A, ETACS - Diagnostic Trouble Code Chart

Go to Step 2

STEP 2. Using scan tool (M.U.T.-IIISE), DTC check list.

Check the ETACS-ECU service items related to the central door locking system operation.

(1) Turn the ignition switch to "OFF".

(2) Check the input signal related to the central door locking operation.

Turn the ignition switch to "ON".
Check the ETACS-ECU service items related to the central door locking system operation.

Door lock switch: Unlock → Lock.

Item No.	Item name	Normal condition
94	Driver's door unlock switch	Unlock → Not unlock

Door lock switch: Lock → Unlock.

Item No.	Item name	Normal condition
94	Driver's door unlock switch	Not unlock → Unlock

Central door lock switch (built in power window main switch or power window sub switch)

Item No.	Item name	Normal condition
100	Central door lock switch	OFF to ON (Only when switch is operated)
101	Central door unlock switch	OFF to ON (Only when switch is operated)

OK: Normal conditions are displayed for all the items.

Is the check result normal?

: Go to Step 3

: Refer to GROUP 54A, ETACS - Inspection Procedure 4: The front door lock actuator (driver's side) signal is not received

: Refer to GROUP 54A, ETACS - Inspection Procedure 21: The door lock switch (incorporated with the power window main switch or power window sub switch) signal is not received

STEP 3. Check of short to power supply, short to ground, and open circuit in +B2 line between ETACS-ECU connector and fusible link.

Is the check result normal?

Go to Step 4

Repair the connector(s) or wiring harness.

STEP 4. Central door lock switch check.

Check that the central door lock switch is in good condition. Refer to Central Door Lock Switch Check

Is the check result normal?

: No action is necessary and testing is complete.

Replace ETACS-ECU.