Hello,
I have posted about this before with no luck and would like to try and resolve the issue. I have a 1988 740 turbo wagon. The problem is unless I turn on the headlights there is a ringing, like if you leave the key in the ignition or open the door. I can stop this by putting in the console lights fuse, fuse #5 in my car, but with the fuse in the headlights are always on even if I turn off the car. One more thing that may be of help is that there was a yellow wire with a black stripe that had burned up, I think that is what blew the fuse to begin with. I have tracked down the wire a bit and can't find any sign of the wire being bare as to ground out or touch something else. Aleekat had led me to a website about stereo installation but it was of no help for my situation. Any information or help would be very much apprectiated. Thank you for reading this post.