Mercedes C-Class door locking problem

I have Mercedes-Benz C-Class Estate (2009 model) that has developed a door locking issue. Earlier this year the driver's door would occasionally not open unless I pressed the key fob repeatedly. Our local mechanic couldn't identify a problem. I took it to a Mercedes-Benz specialist and they said it could be a door actuator.

It seems to only play up once a month or so, but now the front passenger door has stopped working. Not sure if I want to spend £1100 on a "possible" cure. Are you aware of this problem? Is there any other fixes I could have missed?

Asked on 1 September 2016 by Silversalmon

Answered by Honest John
If the lock servos are sticking it's possible that a squirt of WD40 will free them off, providing there is some way of gaining access, such as a removable grommet. WD40 cans come with an extended nozzle for jobs like this.
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Neatly styled estate. Very comfortable and refined. Impressive CDI diesels are economical. Good sized useable boot space.

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