I finally got this fixed over the weekend. This might be over kill, and there may be faster ways to do it, but I have a tendency to want to clean things up if I have them apart. Here's a short list of things that may help others.

- remove the glass from the scissors and door - not too difficult and covered in the widely available manuals.
- I had to remove the motor while still attached to the scissors in the door. I could not remove the assembly as one unit. There might be a magic set of contortions, but I did not discover them.
- I tested the old motor with a power supply, dead as door nail.
- Motor disassembly and testing did not reveal any obvious defects
- I found a nice replacement on ebay - many choices - the motor seems to be used in Mercedes vehicles as well.
- I did not need to cut the wires - just use a small pick to pinch the 'ears' inward so the female connectors will slide out of the plastic housing. They are easily reformed by sliding them on the switch male connectors.
- cleaning and lubricating everything resulted in much smoother operation - time to do the other doors!

Thanks.

I have a 89 245 with same problem

being a bit of a hillbilly I whacked motor with rubber mallet , has been operational now for 2 plus years.

Good luck

Bump

Just replace it with a good used unit.