I've got a 00 A4 Avant wagon. I know about replacing the batteries in the remote key BUT is there a battery in the car itself that needs to be replaced?? What's confusing me is my Audi manual shows an image of an arrow pointing to a cassette holder in my center console next to the e-brake and indicates that there's a battery under there as well. Problem, I don't have that cassette holder, I have a 2-cup, cup holder there. And when I pulled it up I don't see any batteries. Anybody know???