There really aren't enough posts on how people actually fixed or resolved their problems. I'm guilty of this too. Once I've found the cause of my troubles I usually go off, happy motoring, without letting everyone know what worked.

1990 244DL

So, I had intermitant power window troubles. The driver's window always worked. The front passenger window would only work occasionaly. the passenger rear always worked and the driver rear occasionally worked. Two weeks ago I took apart the dash to get to the power window realay - pulled a few relays from the pick and pull (by me the owner lets me test parts I pull before I buy them) and with each relay I tried the problems stayed the same. So it wasn't the relay. My friend suggested swapping the switches from a door that worked to one that didn't. So I thought about it and decided to swap just the switches located in the driver's control panel. That worked. When I moved the switch from the rear passenger position to the front passenger position - it resolved the problem. Now all I have to do is get a few switches from the auto salvage yard and all the windos will work. I just wish I'd tried this before taking the passenger door apart to check if the wires going to the motor were loose. Oh well, live and learn.