I've got a 98 A4, and one day my headlights, wipers, blinkers, and my fan (a/c, heat, etc..) all went out. along with my gear indicator and temp. lights. I brought it in and they said it was a bad wire in the ignition switch, so they replaced that, and everything works now... only now my tiptronic won't work at all, 4,3, and 2 gears as well. My gear indicator lights are all on, basically saying Im in every gear at once, and the car won't shift into fifth gear no matter what I do... I brought the car back and they said something was wrong with my radio and that was causing it all. Only I've had the radio for over 2 years with zero problems. It was professionally installed too. Could tapping into the wrong circuit for the radio do this?? and why would it work for that long? They said they won't fix it unitl I get the radio fixed, but I don't think there is anything wrong with it.. what should I do??

 

dude i hav the same problem and my radio was out to but i replace it with a custom one but my gears still dont work

 

When electrical power is interupted for more than about 5 minutes you have to follow the following procedure to get the transmission out of "limp" mode which is what you describe.

1.perform adaptation of Throtttle Valve Control Module
2.perform adaption of Kick Down function
3. read DTC codes and act accordingly
4.erase DTC codes
5.reset readiness code
Anyone with a vag com should be able to acccomplish these procedures for you.
For more details, see page W27-2 of Bently manual.