Inspection Procedure O-5

The ETACS-ECU does not receive any signal from the driver's door lock key cylinder switch.

All Door Switches Input Circuit Part 1:

All Door Switches Input Circuit Part 2:

CIRCUIT OPERATION
The ETACS-ECU operates the central door locking system according to signal from the driver's door lock key cylinder switch.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the systems, which are described in "CIRCUIT OPERATION", do not work normally.

TROUBLESHOOTING HINTS
- The driver's door lock key cylinder switch may be defective
- 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 Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: MUT-III USB Cable
- MB991911: MUT-III Main Harness B




STEP 1. Check driver's door lock key cylinder switch connector E-01 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is driver's door lock key cylinder switch connector E-01 in good condition?

YES: Go to Step 2.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.










STEP 2. Check the driver's door lock key cylinder switch.
Disconnect door lock key cylinder switch (LH) connector E-01. Then check continuity between the switch terminals.

Q: Is the driver's door lock key cylinder switch in good condition?

YES: Go to Step 3.

NO: Replace the driver's door lock key cylinder switch. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.

STEP 3. Check the ground circuit to the driver's door lock key cylinder switch.Test at driver's door lock key cylinder switch connector E-01.




1. Disconnect driver's door lock key cylinder switch connector E-01 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 equal 2 Ohms or less.

Q: Is the measured resistance 2 Ohms or less?

YES: Go to Step 5.

NO: Go to Step 4.







STEP 4. Check the wiring harness between driver's door lock key cylinder switch connector E-01 (terminal 2) and ground.

NOTE: Also check intermediate connector C-17 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connectors C-17 is damaged, repair or replace the damaged component(s) as described in Harness Connector Inspection.

Q: Is the wiring harness between driver's door lock key cylinder switch connector E-01 (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. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.




STEP 5. Check ETACS-ECU connector C-227 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connector C-227 in good condition?

YES: Go to Step 6.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.










STEP 6. Check the wiring harness between driver's door lock key cylinder switch connector E-01 (terminal 1 and 3) and ETACS-ECU connector C-227 (terminal 25 and 42).

NOTE: Also check intermediate connector C-17 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connectors C-17 is damaged, repair or replace the damaged component(s) as described in Harness Connector Inspection.

Q: Is the wiring harness between driver's door lock key cylinder switch connector E-01 (terminal 1 and 3) and ETACS-ECU connector C-227 (terminal 25 and 42) in good condition?

YES: Replace the ETACS-ECU. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.

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. If the systems, which are described in "CIRCUIT OPERATION", work normally, the input signal from the driver's door lock key cylinder switch should be normal.