1996 Mercedes-Benz S420 Q&A

1996 Mercedes-Benz S420 Question: Power door locks and trunk lock

My power locks and trunk won't lock. I have to manually lock doors and strap trunk down. I checked all the fuses and changed the battery. What else can it be? -
Answer 1
the doors locks and trunk soft-close are both controlled by electric vacuum pumps. central lock pump is under the rear seat and the trunk closure pump is in left side of trunk. either bad pump or a leak somewhere in the vacuum hose nightmare. -
Comment 1
what is the next step to fix this issue. i have the same issue with my s420 Benz. It just don't work after the head light goes out than I replace the head light. I don't understand it at all. any advise please? -
Related Items:
Problems with the pneumatic system can cause closing assist and door lock issues.