So, you push up on your BMW Window Switch and…nothing. Push down on the BMW window switch and…nothing. Sounds like you’re in need of a new BMW window switch. The power window switch in your car signals a relay that you’re ready to roll the window up or down. The relay then sends electricity to the power window motor, telling it which direction in which to roll the window. When everything works, you either get fresh air or a nice, quiet, closed window.

When things don’t work so well, you have a couple of places to check. If your BMW window switch checks out okay, you could have a blown fuse on your power window circuit. It’s also possible that the power window relay is bad, or the motor has burned out. If you find it’s a fuse, make sure you find out why the fuse blew too—a short in your BMW window switch can cause the replacement fuse to blow too, and you’re right back where you started.