Indication Of The Status Of The Doors, Hatches And Lock Motors

There can be up to three contact breakers in the side door lock units: 

• contact breaker which indicates if the door is not closed
• contact breaker to indicate that the central locking motor is in the locked position
• contact breaker for whether the child safety lock motor is in the locked position.

Each contact breaker provides a ground connection on an input to the rear electronic module (REM) when the contact breaker is closed.

Contact breaker for open door indication is used: 

• to generate a message on whether a door is opened during the journey
• to indicate to the rear electronic module (REM) whether or not the vehicle is ready for locking (depending on lock configuration)
• to activate and trigger the alarm function if installed in the vehicle.

Contact breaker for central locking motor indication is used to check whether locking or unlocking has been successful or not.

Contact breakers for child safety locks are only available in the rear doors and indicate that the child safety lock is activated.

There is only one contact breaker in the lock unit in the tailgate/trunk lid. This indicates whether the tailgate/trunk lid is open or closed.

The signals are also used to activate the locking and alarm function, for example if locking takes place while a door is still open. If the central locking is locked and a door is open then a light signal will come on, and the alarm will be activated when the last door is closed.

If the vehicle is equipped with an alarm then there is also a contact breaker at the hood. However, this has no role in the central locking system, but the contact breaker is used to trigger the alarm if installed.