my 1990 300TE has just started to do that, the drivers side window is acting funky. Won't go up mostly, only at times...I think it's the switch on the console...sometimes it's fine. If it conks out completely I'll just switch the passenger window switch over, that'll probably solve it. And then go find another switch at a junk yard, and I don't even know if the rear window switches will work for the front doors, with the auto lowering and such...anyway...I would work that one by swapping parts first...good luck