Hi all, the front windows in my 530i had issues going up but were fine going down, so I went to the Euro Wreckers and priced up some replacements... $195 each
So I thought i'd check them out myself. I removed the passenger window regulator assemly first and played around with it a bit trying to work out what was stopping the window from winding up on it's own accord and the conclusion I came to was that something internally in the motor was slipping.
I tried a number of things in an attempt to fix it initially but nothing worked.
I needed to remove the cap covering the motor before I could go any further. It popped off nice and easy and I examined the internals finding that there is a clutch type mechanism that must (when in good working order) give a smoother more seemless operation, especially when it reaches it's lowest and highest points?
Anyway, the rubber blocks under the metal disc that is pressed onto the spline must have worn out and it certainly looked like more trouble than it was worth to replace them. I also didn't want to be spending near on $200 a pop for 2nd hand replacements...
The fix was quite a simple one.... Three self tapper screws in each motor as per the pics below. The screws are only about 3mm x 25mm and they are just simply screwed through the metal disc, through the rubber blocks and into the plastic gear... And whalla... Windows now go up again!!
My 6year old took a pic of me working on the window...
The screws in question. On the sill plate for size reference.
Part way to the fix..