Models known to be affected: Saab 900 (1994-98), Saab 9-3 (1998-2003),  Saab 9-3 SS (2003+), and Saab 9-5 (1998+)

Having already bought a used Saab CD changer off of eBay before, potential buyers should know of a problem that many sellers, either not knowing about or choosing not to disclose, don't mention in their listings. In order to work in your own car, the stereo components from these cars need to be "divorced" from the cars they were originally installed in, or as a security feature they will not work when installed in another car. This "divorce" procedure, which can only be done with a Saab technician's computer, has to to be done or else the changer will not be recognized by the car's computer. Be sure before bidding you know if the changer has been properly disassociated from the original car, or else you could end up paying for an expensive install and uninstall of a locked cd changer as I did.