Mercedes-Benz vehicles such as E, C, S, ML, GL, 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 causing the door lock to bounce up and down several times.
There is 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.
What you need to do is to apply a small amount of tape to the door lock pin.
1. Remove the door pin or at least pull it up in the unlock position.
2. Take 1 inch of electrical tape and apply it around the door lock pin.
3. Ensure the door pin can go up and down.
4. Take your Mercedes-Benz for a test drive. Your door lock should not bounce up and down anymore.
The way that this fix works is 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.
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