Driver's Door Lock

Drivers Door Lock Actuator






















The driver's door lock provides the following familiar signals to the General Module:
- Lock/Unlock,
- DWA arm/disarm
- Convenience closing and opening signals.

It also provides a mechanical link to manually lock/unlock the actuator in the event of a failure.

The GM monitors these key positions over two wires. The signals are generated by two hall effect sensors (Hall Sensor 1 & 2) located in the actuator.

When the key is turned, a plastic cylinder in the lock actuator is simultaneously rotated by the lock tumbler extension rod. An asymmetrical shaped magnet is incorporated in the plastic cylinder; which when rotated changes the magnetic influence on the hall sensors. The presence of a magnet in close proximity to the sensing surface of either hall sensor creates a coded input over the two wires that the GM uses to determine the key position.

- Magnet in front of sensor, current flow through the sensor is < 5 mA (0).
- Magnet rotated away from sensor, current flow through the sensor is > 12 mA (1).

Hall effect sensors improve the actuators reliability since they are impervious to moisture and there are no wear contacts.

- Key in the neutral position, both sensors are simultaneously influenced by the magnet - 0/0.
- Key turned to the unlock position from neutral, hall sensor #1 magnet segment moves away from hall sensor - 1/0.
- Key turned to lock position from neutral, hall sensor #2 magnet segment moves away form hall sensor - 0/1.

Hall sensor 1 & 2 are not included in the front passenger door or rear door actuators.

There are two motors incorporated in each actuator that provide two separate functions:

- Single lock/unlock function. Also known as central lock, this motor controls the mechanical lock mechanism when the central lock button is pressed to single lock the vehicle. The lock mechanism is fully locked at this point but can still be opened from the interior by pulling the appropriate interior door handle twice or by pressing the central lock button again. When single lock function is activated, the fuel filler flap actuator is not locked.

- Double lock/unlock function. Also known as central arrest, this motor is activated only when the vehicle is locked from the outside at the driver's door lock with a key or when the GM receives a lock request from the FZV system. In this case the double lock motor is activated simultaneously with the single lock motor. The function of the double lock motor is to mechanically offset an internal rod disabling it from unlocking the vehicle from the interior. This prevents the doors from being unlocked by any means except from an unlock request at the driver's door or via the FZV remote key.


NOTE: This component has been disassembled to provide functional understanding. This component does not contain any replaceable parts and will void it's warranty if disassembled.

Door Contact Hall Sensor







Also included in the drivers door actuator is a third hall effect sensor. This sensor signals the door open/closed status to the GM. This sensor replaces the door jamb mechanical switch of previous systems. The rotary latch plate position activates the door contact hall sensor.

- When the door latch is closed, current flow through the sensor is < 5 mA (0).
- When the door is open, current flow through the sensor is > 12 mA (1).

The passenger side front door and both rear door lock actuators only include this hall effect sensor (hall sensor 3). Hall sensors 1 & 2 are not required.

Lock Actuator Control


Control During Double Lock:







Control During Single Lock:







Control During Unlock







All door lock actuators and the fuel tiller flap actuator are controlled directly by the GM via four internal load relays. The drivers door lock actuator has a separate circuit for the selective unlocking feature. If this feature is disabled by key memory encoding, the driver's door lock actuator selective unlock circuit is activated simultaneously with the balance of the motors during unlock.