12.3 Central Locking System

There are two electrical components of the central locking system-the bi-pressure pump in the luggage compartment and the master activator switch in the driver's door. The master activator switch controls the electrical signal to the bi-pressure pump. If the pump does not run when the door key is turned, test the electrical portion of the system as described below. If the pump runs, but the system does not operate, test the bi-pressure system as described in BODY AND INTERIOR.

To test the system, remove the bi-pressure pump from its housing as described in BODY AND INTERIOR, and disconnect the pump's harness connector. Place the driver's door lock button in the up (open) position. There should be voltage at the pump's harness connector as shown in Fig. 12-2. Place the driver's door lock in the down (locked) position. There should be voltage at the pump's wiring connector as shown in Fig. 12-3. If these conditions are not met, test the switch and the circuit wiring. See CURRENT FLOW DIAGRAMS. The inside door trim panel must be removed as described in BODY AND INTERIOR to reach the master activator connector.

Fig. 12-2.

Test light (shown schematically) connected between terminals of central locking system's bi-pressure pump harness connector for checking for voltage from master activator in driver's door (open position).

Fig. 12-3.

Test light (shown schematically) connected between terminals of central locking system's bi-pressure pump harness connector for checking for voltage from master activator in driver's door (locked position).