85 SEL Electrical Questions
 

Just picked up a 84 500SEL European model. Question I have is regarding windows and seat adjustments. It seams that with or without the key in the ignition, the windows and seat adjustments work fine. As soon as door is closed, even with car running, windows and seat adjustments do not work. It has something to do with button on side of door that is depressed when door is closed. How can I fix this?

Jeff
Boston, MA

Normal for your car...my Euro 380 did this, it is normal and is mentioned in the euro manual...i like the feature a lot

I think Jeff's problem is that those items don't work when the key is in the on position. That's definitely not normal.

There might be a problem in the power separation relay (code E?) that decides whether the seats and windows get power because a door is open or because the key is on. I believe that relay is in the main fuse box. In a US car I believe it's the relay along the passenger side edge of the fuse box second from the front. So two rows of fuses, one relay, then the power separation relay.

This might help identify the relay -- have someone open and close the driver's door as you feel which relay clicks. Hopefully one and only one clicks.

Hope that helps.

Sixto
91 300SE
87 300SDL
83 300SD ... any takers at $1100? Seats and windows work :)

The button between the left front and rear window switches is a lock-out switch. In one position all windows work, in the other position only the driver's window works.

Sixto
91 300SE
87 300SDL
83 300SD ... any takers at $1100?

whoops...gotta work on my reading skills! sorry

There also is a diode that is used in separation. It is located in the fuse box. Looks like a two pin relay, about the size of the later spade type fuses.

US cars also allow the seats to be adjusted without the key when the doors are open. The difference isthe windows and sun roof. FWIW, part of the DOT conversion that was supposed to be done on that car required neutering those functions. The wat that was done often causes long term problems.

If you live around MBs long enough you can come across some real ironies. When my wife bought her US-BUILT ML320 I was dismayed to find that seat function was removed. The key now had to be turned on to move the seat which was a PITA when my wife has the seat all the way forward and I am going to drive. I lived with it.

A couple years go by and I am exploring and I find that the ability to control the seats without the key on IS a programmable function of the AAM (all activities module). BUT, BUT, it is emphatically stated that this is not to be done. So I did it, and I found out why. The dumkaufs produced a car in the US with only european style controls; the windows and the sunroof are thus also activated and little Bobby can now chop off little Jill's head with the door open and the key off.