1996 Mercedes-Benz S420 Q&A
1996 Mercedes-Benz S420 Question: Power door locks and trunk lock
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. - overbys
Problems with the pneumatic system can cause closing assist and door lock issues.