I've got a problem on my W140 coupe. Like the saloon, you just pull the door most of the way shut, and then it closes itself. However, unlike the saloon (I think) it's pillarless, and the window is frameless.

When you open the door, the front and rear windows both open very slightly. When you close the door, the windows close again as the door pulls itself shut. Or that's the theory. Usually it works in my car, but sometimes the window doesn't close, so I have a 1/8" gap. It also sometimes seems that the door might not be closed properly.

Does anyone have any idea what the problem might be?

 

So is the door closing properly or not? You have to answer that first. I don't know exactly, but there must be a microswitch that the door hits when it closes to tell the car that the door has closed and the windows can go up now. It's probably in the latch mechanism somewhere, and it probably has an adjustment. Adjust the switch properly, and everything will probably work again.

Brett