Lock Units Side Doors

Fig 1: Identifying Lock Units With Quick Lock Functionality

Courtesy of VOLVO CARS CORPORATION

The lock units (3/74-77) are in the doors and are directly connected to the door control module in the relevant door. There are different versions of the lock units, depending on the configuration of the lock motors.

There are four versions of the lock units in the front doors with lock motors for:

• central locking
• central locking and deadlocking
• central locking and quick locking
• central locking, deadlocking and quick locking.

The central locking lock motor locks the door.

The quick lock motor is hardwired to the keyless vehicle module (KVM) and opens the door upon receipt of a command from the keyless vehicle module (KVM).

The door control modules can only activate the lock motors on receipt of a command from the central electronic module (CEM).

In addition to the lock motors, the lock units contain up to three contract breakers depending on the configuration:

• contact breaker to indicate that the central locking motor is in the locked position
• contact breaker which indicates that the door is not locked

The lock motors have built in overheating protection which prevents the motor from activating if there is a risk of the motor getting too hot.

When the quick locks are activated by the keyless vehicle module (KVM), the catches in the standard lock units are released from the striker plates in the car body. The quick locks contains a switch which is acted on by a control arm from the door handle. This switch is closed when the door handle is pulled out fully. This switch must be closed for the keyless vehicle module (KVM) to activate the quick lock.