My passenger side electric window on my 2003 mini-s works fine in cold weather but as soon as the temperature goes over 50f it will not retract (go down) I bot the car in June and noticed it did not work. I didnt get around to having it looked at until November and found it worked fine and continued to all winter.
On Friday, 3/18, the first really nice day, it didnt work again. SUnday morning it was in the 30s and it worked fine. The drivers side works fine all the time.