Pinpoint Test D: All Door Locks Are Inoperative From One Switch

WARNING: This page is about a different car, the 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

Refer to appropriate SYSTEM WIRING DIAGRAMS article, Power Door Locks for schematic and connector information.

Normal Operation

Voltage is supplied to the door lock control switches at all times through circuit 1524 (DB). The door lock control switches provide voltage to the driver door module (DDM) through circuits 119 (PK/YE) and 120 (PK/LG) for the lock and unlock requests, respectively. When the lock or unlock switch is pressed, the voltage signal is routed to the DDM.

The DDM contains internal relays that are energized depending on input received. When the DDM receives a lock or unlock request from the door lock control switch, the DDM energizes the appropriate relay(s) to lock or unlock the doors.

This pinpoint test is intended to diagnose the following:

Wiring, terminals or connectors
Door lock control switch

PINPOINT TEST D: ALL DOOR LOCKS ARE INOPERATIVE FROM ONE SWITCH

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

D1 CHECK CIRCUIT 1524 (DB) FOR VOLTAGE
- Disconnect: Inoperative Door Lock Control Switch
- Measure the voltage between the LH door lock control switch C505-4, circuit 1524 (DB), harness side and ground; or between the RH door lock control switch C605-4, circuit 1524 (DB), harness side and ground.
- Is the voltage greater than 10 volts?
1. YES : INSTALL a new door lock control switch. REFER to Door Lock Control Switch . TEST the system for normal operation.
2. NO : REPAIR the circuit for an open. TEST the system for normal operation.