My wife has a '98 A4 w/ 6 cyl. Yesterday the air conditioner shut off on her. I went out to the garage to check it out when she got home and there is a "scratchy pulley" sound coming from the engine compartment. In addition, when you turn the key back one to the accessory position the engine does not shut off and the fan then kicks in in the interior.

Where to start with this one?