i found mine by trial and error. first i replaced the blown fuse and promptly blew it again. then i pulled the fan motor out and found it had seized up from frozen condensation in it. this seems to have burned out one of the circuits on the resistor. i completely disassembled the fan, lubed it and put it back together, not really too hard. course, the wife was ticked i did it on the kitchen table while she was putting out cookies to cool. apparently too many cookies diappeared while the (oops, off topic)when i pulled the resistor out, i could see one of the circuits was broken. it ran ok on all speeds except #3; but switching from 2 to 4 blew a fuse every time. i took the glove box out and that made the whol thing quite simple. yes it is dealer item only and yes st. charles is the place to go.