I have a '96 A6, fwd and it was behaving perfectly until I had to have the ignition switch replaced. I have since replaced it again as well as the key and housing (I have the scars to prove it). The new switch had the same number as the old only it is an 849 "B" instead of just 849. Now the radio shuts off after an hour, the interior lights don't come after the key is removed from the switch, key chime doesn't work (not all bad), airbag light stays on, other little things. I have resorted to removing the airbag light and just living with it. I'm told the only part available is the 849"B" as it supercedes the old part. I cannot believe the car can't be made right. It runs great otherwise very happy with her. But I know it's not right and I'd love to be able to fix it. If anyone has any ideas I open to trying just about anything reasonable. Thanks!!!!