I was wondering if someone could directly explain how to test the PSE box... before I say that, let me express that the door assist does work, but I lifted the seat and found the hoses and the pump, but I think it has nothing to do with the Door assist. I could be wrong I didnt hear anything from the box under the seat, the sound I heard from the door closing assist was from the trunk. I cant get the central locking to lock the doors. I just wondered before I go hunting for the box, if there was a way to test it on a volt meter. If anyone has a wiring diagram so I know which pins to test would be good. I checked all the fuses trunk and hood but no burnt fuses. I hope I can figure out a way.

If there is something Im missing I would be grateful if someone can tell me what to do or look for. I dont want to goto a dealer if I can do it myself. I would not want to wait 4 hours for a guy to say "Yea you need a new control Box" its like duh!

 

Flip the pump under the seat over and pry the bottom off with a small flatblade screw driver, make sure the rubber hose at the pump in the unit is still on. If its off, reinstall it using a small zip tie for a clamp. put it back together and unplug the electrical connectors and then reconnect them to reset the unit. I've seen a lot of these hoses come loose. this pump also runs the lumber supports in the front seats and the trunk closing handle, Closing assist uses a totally different pump. Hope this helps

 

hello,
i had the same problem with my 93 300SE central locking system vacuum pumplocatedunder the rear right seat cushion.. The symptoms you're experiencing with your pump i had the same thing only except when the last time the pump it went it blew the fuse on me.I replaced the fuse and tried it again an nothing just the rear headrests worked nothing else, no alarm, no central lock system, no reverse parktronic antenas and no lumbar suports.., ( the unitgave up its last minute) i replaced it with another unit now everything works fine..let me know if you're looking for onecause i have my cousin parting out his 97 S420 due to his tranny went and dealer asking him $ 3500 to fix it..

the pic shows the right pump that controls all these features..

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