Regarding my 91 318i:
I replaced my wiper motor about 3 months ago. It had fried itself, getting hot enough to melt the plastic shield that goes over it. IIRC, I had left the car to warm up(I'm in AK) and when I returned I smelled the smell of plastic cooking and the wipers didn't work.
So I replaced the motor, all seemed well, then tonight I stopped to do some work, left the car idling under the car port, and when I came out after about 10 minutes the motor was smoking, and again no wipers.
Can this happen just due to friction from a dry, but warm windshield? Are these motors prone to self destruction?
I do NOT look forward to doing that replacement again.