4. All Doors Do Not Lock/Unlock With Key Or Inside Lock Knob LH

CIRCUIT OPERATION
When the front door inside door lock knob (front door lock actuator switch [LH]) is operated to the lock or unlock side, the ETACS-ECU will output the door lock or unlock signal for 0.5 seconds. signal for 0.5 seconds. If the door lock key cylinder [LH] (Door lock key cylinder switch [LH]) is operated to the lock or unlock side, the ETACS-ECU will output the lock or unlock signal for 0.5 seconds.

TECHNICAL DESCRIPTION (COMMENT)
The cause may be a malfunction of the front door lock actuator switch [LH] circuit, of the door lock key cylinder switch [LH] circuit or of the ground circuit.

TROUBLESHOOTING HINTS
- Malfunction of the front door lock actuator switch [LH]
- Malfunction of the door lock key cylinder switch [LH]
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991502: Scan Tool (MUT-II)
MB991529: Diagnostic Trouble Code Check Harness

CAUTION: To prevent damage to the scan tool MB991502, make sure the ignition switch is "OFF" before connecting or disconnecting the scan tool MB991502.

STEP 1. Check the ETACS-ECU input signal. Using either the scan tool or a voltmeter

- Using the scan tool MB991502
1. Connect scan tool MB991502 to the data link connector.
2. If the tone alarm of scan tool MB991502 sounds once when the front door lock actuator switch [LH] or the door lock key cylinder switch [LH] is operated (lock/unlock), the ETACS-ECU input signal for that switch circuit system is normal.

- Using a voltmeter
1. Use special tool MB991529 to connect a voltmeter between ground terminal 4 or 5 and the ETACS-ECU terminal of the data link connector.
2. If a voltmeter indicator deflects once when the front door lock actuator switch [LH] is operated (lock/unlock) or the door lock key cylinder switch [LH] is operated (lock/unlock), the ETACS-ECU input signal for that switch circuit system is normal.
If the input signal of the front door lock actuator switch [LH] is not normal, go to Step 2.
If the input signal of the door lock key cylinder switch [LH] is not normal, go to Step 3.

STEP 2. Check the front door lock actuator switch [LH] continuity.
1. Remove the door latch assembly.

2. Check the continuity when the door lock actuator switch [LH] is operated (lock/unlock).
If the front door lock actuator switch [LH] is damaged, replace it. Then go to Step 8.
If the front door lock actuator switch [LH] is not damaged, go to Step 4.

STEP 3. Check the door lock key cylinder switch [LH] continuity.
1. Remove the door lock key cylinder switch.

2. Check the continuity when the door lock key cylinder switch [LH] is operated (lock/unlock).
If the door lock key cylinder switch [LH] is damaged, replace it. Then go to Step 8.
If the door lock key cylinder switch [LH] is not damaged, go to Step 4.

STEP 4. Check the harness wires between ETACS-ECU connector C-81 and front door lock actuator switch [LH] connector E-15.
1. Remove the instrument panel side cover [LH].
2. Check the harness wires between ETACS-ECU connector C-81 and front door lock actuator switch [LH] connector E-15.
If any harness wire between ETACS-ECU connector C-81 and front door lock actuator switch [LH] connector E-15 is damaged, repair it. Then go to Step 8.
If the harness wires are not damaged, go to Step 6.

NOTE: After inspecting intermediate connector C-67 or C-68, inspect the wire. If intermediate connector C-67 or C-68 is damaged, repair or replace it. Refer to Harness Connector Inspection. Then go to Step 8.

STEP 5. Check the harness wires between ETACS-ECU connector C-81 and door lock key cylinder switch [LH] connector E-14.
1. Remove the instrument panel side cover [LH].
2. Check the harness wires between ETACS-ECU connector C-81 and door lock key cylinder switch [LH] connector E-14.
If any harness wire between ETACS-ECU connector C-81 and door lock key cylinder switch [LH] connector E-14 is damaged, repair it. Then go to Step 8.
If the harness wires are not damaged, go to Step 7.

STEP 6. Check the harness wires between front door lock actuator switch [LH] connector E-15 and ground.
If any harness wire between front door lock actuator switch [LH] connector E-15 and ground is damaged, repair it. Then go to Step 8.
If the harness wires are not damaged, replace the ETACS-ECU. Then go to Step 8.

NOTE: After inspecting intermediate connector C-68, inspect the wire. If intermediate connector 0-68 is damaged, repair or replace it. Refer to Harness Connector Inspection. Then go to Step 8.

STEP 7. Check the harness wires between door lock key cylinder switch [LH] connector E-14 and ground.
If any harness wire between door lock key cylinder switch [LH] connector E-14 and ground is damaged, repair it. Then go to Step 8.
If the harness wires are not damaged, replace the ETACS-ECU. Then go to Step 8.

NOTE: After inspecting intermediate connector C-68, inspect the wire. If intermediate connector C-68 is damaged, repair or replace it. Refer to Harness Connector Inspection. Then go to Step 8.

STEP 8. Check symptoms.
Confirm that the intermediate connectors, the harness wires, the ETACS-ECU, the front door actuator switch [LH] and the door lock key cylinder switch [LH] are normal.