One Door Fails To Lock & Unlock From Any Switch

Possible Causes:

• Door Lock Motor - Open
• Lock Relay Output Circuit Open
• Driver Door Lock Motor - Open
• Driver Unlock Relay Output Circuit Open
• Lock Relay Output Circuit Open
• Unlock Relay Output Circuit Open
• Driver Door Unlock Relay Open

Testing

1. If problem is with driver door, go to next step. If problem is not with driver door, go to step  5 .
NOTE: This test is for a driver door lock motor that is completely inoperative. If driver door lock motor only fails to lock, perform DRIVER DOOR FAILS TO LOCK FROM ANY SWITCH  test. If driver door lock motor only fails to unlock, perform DRIVER DOOR FAILS TO UNLOCK FROM ANY SWITCH  test.
2. Turn ignition off. Disconnect driver door lock motor/ajar switch connector. Connect a 12-volt test light between driver door lock motor/ajar switch connector terminal No. 3, driver door unlock relay output circuit (Dark Blue wire) and terminal No. 4, door lock relay output circuit (Orange wire). See Figure . Observe test light while pressing door lock switch to lock and unlock positions. If test light flashes when door lock switch is pressed, replace driver door lock motor. See POWER DOOR LOCKS & TRUNK RELEASE - CONCORDE, INTREPID & 300M article. If test light does not flash when door lock switch is pressed, leave driver door lock motor/ajar switch connector disconnected and go to next step.
3. Remove driver door lock relay from junction block. Measure resistance of door lock relay output circuit (Orange wire) between door lock relay connector terminal No. 81 and driver door lock motor/ajar switch connector terminals No. 85 and 86 at driver door unlock relay (component side). See Figure and Figure . If resistance is less than 5 ohms, leave driver door lock motor/ajar switch connector disconnected and go to next step. If resistance is 5 ohms or more, repair open in Orange wire.
4. Remove door unlock relay from junction block. Measure resistance of door unlock relay output circuit (Dark Blue wire) between door unlock relay connector terminal No. 76 and driver door lock motor/ajar switch connector terminal No. 3. If resistance is less than 5 ohms, replace door unlock relay. If resistance is 5 ohms or more, repair open in Dark Blue wire.
5. Turn ignition off. Disconnect suspect door lock motor/ajar switch connector. Connect a 12-volt test light between door lock motor/ajar switch connector terminal No. 3, door unlock relay output circuit (Pink/Black wire) and terminal No. 4, door lock relay output circuit (Orange wire). See Figure and Figure . Observe test light while pressing door lock switch to lock and unlock positions. If test light flashes when door lock switch is pressed, replace suspect door lock motor. See POWER DOOR LOCKS & TRUNK RELEASE - CONCORDE, INTREPID & 300M article. If test light does not flash when door lock switch is pressed, leave door lock motor/ajar switch connector disconnected and go to next step.
6. Connect scan tool to Data Link Connector (DLC). Connect a 12-volt test light between ground and suspect door lock motor/ajar switch connector terminal No. 4, lock relay output circuit (Orange wire). Using scan tool, actuate door lock relay. If test light does not flash, repair open in Orange wire. If test light flashes, leave door lock motor/ajar switch connector disconnected and go to next step.
7. Connect 12-volt test light between ground and suspect door lock motor/ajar switch connector terminal No. 3, unlock relay output circuit (Pink/Back wire). Using scan tool, actuate door unlock relay. If test light does not flash, repair open in Pink/Black wire. If test light flashes, fault may be intermittent. Check related wiring and connectors for poor connections or damage to wiring harness. See WIRING DIAGRAMS  . Repair any problems found as necessary. If no problems are found, check if any Technical Service Bulletins (TSBs) apply to vehicle. If no TSBs apply, test is complete.