Is your Power Window "off the track", stuck or not working, broken, moving slowly or just drop in the door? The most likely cause is a broken power window regulator or motor. Modern power window regulators are designed with plastic that decomposes at a specific rate. Therefore, they break a lot faster than in previous years. These plastic parts are placed at points in the power window regulator where tension is greatest. When most people have a power window repair problem they think of the dealer first or their local auto shop.