Howdy, folks!
My central locking system wasn't working on my '94 C280 when I bought it (109k m.) Upon investigation, I found the housing of the vacuum pump to be melted around the motor and the fuse blown (motor was apparently fried). The windows and sunroof could be opened/closed with the key in the driver's door, the alarm worked, and I believe the rear windor defogger worked too. I bought a used pump on ebay, which turned out to be the wrong one (Mercedes vs. Bosch) but just for kicks I connected it and tie-wrapped the vacuum plug to it and it worked from the switch in the dash. I sent that pump back and got the correct one. Since installing that one, I can lock and unlock everything from the dash switch but not from the front doors. I have been getting in a back door after parking and using the switch to lock all the doors and the trunk and gas filler cover. The alarm no longer works, the windows and sunroof don't respond to the key in the driver's door any more, and the rear defogger doesn't work either (not really sure if it was working before my "repair"). All the locks respond to unlocking with the key after locking with the switch, but won't lock with the key. Are all these things related? Help!!!!



Thanks in advance!
Bill

 

Well...the rear defroster mystery is solved....operator error. I still don't know the answer to the locking/alarm/window open-close from the door key question though. It seems that I may have read somewhere something about the PSE having to be programmed in order to work. If so, how do I go about accomplishing that? Anybody???