On my wife's Mazda 6s, it was a fan control unit. I would assume we have something similar. In the meantime, if you could locate the fuse, you could just kill power to it completely. I know that in my '00 328i, under the hood, just behind the steering wheel, there is an electrical box. Open the top and you should see several removable relays. When you pull one, certain items on the car lose power.