I am trying to hardwire a radar detector in my new 2007 X3. I'd like to place it on the visor, and attach it to a 'switched' line, so it is off when the car is off.

I tried some of the fuses in the fusebox. But they seem to be 'hot' even when the car is off. For example, I tried a power door window fuse and a heated steering wheel fuse (which clearly are inoperable when the car is off) and both fuses were hot. This doesn't make sense to me. Any explanation?

I have an 03' M3 and an '02 530i, and I was able to wire into an unused connector in the small panel above the windshield, but nothing seems unused, and I'm hesitant to start poking around up there.

Any suggestions would be most appreciated.

Thanks!

Doug

I would suggest just testing the fuses and see which ones are cold when the ignition is off.