Hi everyone! Love Audis, love my A4, but what were they thinking putting radio codes? Anti-theft? Yeah, not in NYC. I disconnected my battery to beef up some stereo components, plugged it back in, and no radio w/o code! I kno wthe procedure, read all about it in the owner's man. Problem: I bought the car in 1998 as a used '97. I guess I'll have to see my dealer...any other suggestions?<br>Thx.

Essentially it is just a 9 volt battery that plugs into the cigarrette lighter. This retains power to the radio while the battery is disconnected. I've seen it available in various catalogs like Imparts, or you could make it yourself.