Mercedes-Benz vehicles such as E, C, S, ML, GL, and R Class are designed to automatically lock the doors as soon as you start to drive.
On those models, the door lock actuators may fail to cause the door lock to bounce up and down several times.
There are a couple of ways to fix this problem.
First, you can replace the door lock actuator, which can cost from $150 to $450 depending on if you try to fix it yourself or have the dealer fix the problem.
The second solution is practically free.
While fixing a faulty door lock actuator can restore proper locking function, diagnosing the root cause of the issue is just as important. The YOUCANIC Full System Scanner helps Mercedes-Benz owners pinpoint door lock and central locking system problems by reading fault codes from the vehicle’s Body Control Module (BCM). This scanner allows you to perform active tests, such as triggering the door locks remotely to determine if the actuators are responding correctly. Instead of unnecessarily guessing or replacing expensive parts, the YOUCANIC scanner provides the data you need to make an informed repair decision—saving you time and money while ensuring your vehicle’s security system functions correctly.
What you need to do is to apply a small amount of tape to the door lock pin.
- Remove the door pin or pull it up in the unlock position.
- Apply 1 inch of electrical tape around the door lock pin.
- Ensure the door pin can go up and down.
- Take your Mercedes-Benz for a test drive. Your door lock should not bounce up and down anymore.
These fixes work by creating resistance at the door lock pin. This prevents the door lock pin from bouncing up and down when you lock the door or when the doors lock automatically.