Door Lock/Unlock Actuator Circuits

The reversible actuators control the power door locks. The power door electrical system controls the actuators by applying battery voltage to one terminal and ground to the other terminal. The MALL supplies this battery voltage and ground when the module receives a door lock or unlock input signal. Normally, the following MALL module connector C1 terminals are both at ground:
- Terminal C
- Terminal A

The MALL module control at the connector C1 terminal C switches to battery voltage in order to lock the doors. The module provides battery voltage to all of the actuators on CKT 295 (GRY). The opposite side of each actuator is connected to the MALL module connector C1 terminal A. The MALL module connector C1 terminal A is still at ground. This grounded circuit path is CKT 694 (TAN) for the LH front door lock actuator. The following components are the grounded circuit path:
- CKT 694 (TAN)
- The normally-closed contacts of the LF door lock isolation relay
- CKT 294 (TAN) for the other three door lock actuators
- The fuel door release solenoid (Pontiac only)

The actuator in each door runs in order to move the door locks to the LOCK position. In order to unlock the doors, the MALL module accomplishes the unlock function in the same way. However the remote function actuator (RFA) module controlled LF door lock isolation relay in this circuit allows for the following three methods of unlocking:
- Only the left front door locks
- All of the doors unlock
- Fuel door unlocks (Pontiac only)

Pressing the UNLOCK button on the keyless entry transmitter provides an unlock signal to the following components:
- RFA module
- MALL module

The RFA module turns on the output at terminal E6. Terminal E6 grounds CKT 1391 (LT GRN). The coil of the LF door lock isolation relay energizes. This opens the normally-closed relay contacts. This action disables the door lock circuit to the following components:
- Right front door lock
- Rear door locks
- Fuel door release solenoid (Pontiac only)

Simultaneously, the MALL module provides battery voltage on CKT 694 (TAN) to the LH front door lock actuator while holding CKT 295 (GRY) at ground. The left front door unlocks.

When the UNLOCK button is pressed a second time (within 5 seconds of the first press), the RFA module turns oft the output at terminal E6. This produces the following effects:
- Removes the ground from CKT 1391 (LT GRN)
- De-energizes the isolation relay

The relay contacts close. This connects CKT 694 (TAN) to CKT 294 (TAN). This action provides battery voltage to the rest of the door lock actuators. Also, this action provides battery voltage to the fuel door release solenoid on CKT 294 (TAN) while CKT 295 (GRY) is still held at ground (Pontiac only). The rest of the doors unlock. Also, the fuel door unlocks (Pontiac only).

The door lock actuators are usually powered for just a moment. If the actuators remain on, an electronic circuit breaker in each actuator opens in order to protect against damage. Each circuit breaker has a positive temperature coefficient which resets automatically when voltage is removed from the actuator.