There are five common reasons why your car door lock is not working.
Mercedes driver door won t lock.
I replaced the vacuum element actuator which did not solve the problem.
Just not unlock driver door.
Got to the car today opened the door and the alarm went on.
2010 c300 driver side door lock actuator was not working and door would not lock i replaced actuator and the door now closes and latches but the actuator still does not work.
The replacement actuator was a mercedes replacement part.
Straightening the linkage solved the problem.
Got home today and when i wanted to lock the car i realised that it doesn t want to lock at all.
I have tried to lock it using the button on the handle i tried to lock it using the remote i have also tried opening it using the actual key.
It will lock unlock all other doors open trunk.
Driver side door won t unlock using remote.
All of the other door lock actuators work.
If your locks arenĂ¢ t working replacing the battery in the key fob could solve the issue.
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I took out the lock mechanism from the door and upon inspection found that one of the metal linkages was twisted.
The key fob battery is dead.
Using the key in the driver door lock would lock all doors except for the driver door.
Opening the driver door while all the other doors were locked would set off the alarm.