Inspection Procedure C-3

INSPECTION PROCEDURE C-3: Central Door Locking System: The Liftgate Lock Does Not Work.

Central Door Lock Circuit (Part 1):

Central Door Lock Circuit (Part 2):

CIRCUIT OPERATION
- The ETACS-ECU controls the liftgate according to the signals below:
- Liftgate handle
- Front door lock actuator
- Door lock key cylinder switch
- Door lock switch, which is incorporated in the power window main switch or front power window sub switch

- The ETACS-ECU controls the liftgate by activating the liftgate actuator based on the input signals.

TECHNICAL DESCRIPTION (COMMENT)
The wiring harness between the ETACS-ECU and the door lock actuator may defective.

TROUBLESHOOTING HINTS
- Trouble in input signal system
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- Liftgate actuator failed
- The ETACS-ECU may be defective

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Check the input signal (by using the pulse check mode of the monitor).

Check the following switches and input signals:
- Liftgate handle

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.






1. Connect the scan tool MB991958. Refer to "How to connect SWS monitor". How to Connect SWS Monitor
2. Operate scan tool MB991958 according to the procedure below to display "Pulse check".
a. Select "Interactive Diagnosis".
b. Select "System Select".
c. Select "SWS".
d. Select "Pulse Checking".

3. Check if scan tool MB991958 sounds or not.






Q: When the liftgate handle is operated, does scan tool MB991958 sound?

Tone alarm of scan tool MB991958 sounds normally.: Go to Step 2.

When the liftgate handle is operated, scan tool MB991958 does not sound.: Refer to Inspection Procedure P-9 "The liftgate handle signal is not sent to the ETACS-ECU". Inspection Procedure P-9

STEP 2. Check liftgate actuator connector F-11 for loose, corroded or damaged terminals, or terminals pushed back in the connector.






Q: Is liftgate actuator connector F-11 in good condition?

YES: Go to Step 3.

NO: Repair or replace the damaged component(s). Verify that the liftgate lock work normally.

STEP 3. Check the liftgate actuator.

Remove the liftgate actuator, and check it.










Q: Does the liftgate actuator work normally?

YES: Go to Step 4.

NO: Replace the liftgate actuator. Verify that the liftgate lock work normally.

STEP 4. Check the ground circuit to the liftgate actuator. Measure the resistance at liftgate actuator connector F-11.






1. Disconnect key liftgate actuator connector F-11 and measure the resistance available at the wiring harness side of the connector.






2. Measure the resistance value between terminal 2 and ground.
- The resistance should be 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES: Go to Step 6.

NO: Go to Step 5.

STEP 5. Check the wiring harness between liftgate actuator connector F-11 (terminal 2) and ground.






- Check the ground wire for open circuit.

Q: Is the wiring harness between liftgate actuator connector F-11 (terminal 2) and ground in good condition?

YES: No action is necessary and testing is complete.

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 the wiring harness as necessary. Verify that the liftgate lock work normally.

STEP 6. Check ETACS-ECU connector C-217 for loose, corroded or damaged terminals, or terminals pushed back in the connector.






Q: Is ETACS-ECU connector C-217 in good condition?

YES: Go to Step 7.

NO: Repair or replace the damaged component(s). Verify that the liftgate lock work normally.

STEP 7. Check the wiring harness between ETACS-ECU connector C-217 (terminal 32) and liftgate actuator connector F-11 (terminal 1).














- Check the communication lines for open circuit and short circuit.

NOTE: Also check intermediate connectors C-30 and F-02 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connectors C-30 or F-02 are damaged.

Q: Is the wiring harness between ETACS-ECU connector C-217 (terminal 32) and liftgate actuator connector F-11 (terminal 1) in good condition?

YES: Replace the ETACS-ECU. Verify that the liftgate lock work 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 the wiring harness as necessary. Verify that the liftgate lock work normally.