Now someone correct me if im wrong, but i assume teh audi does not have a "acc" positive power. Cause if I put my key in the alleged ACC spot, teh radio is off, the only spot where the radio is on is if teh key is in the "on" setting. So one would have to run either a new line from the ignition from the acc spot and connect it to the red wire of the radio. Just my input......someone enlighten me here as i have installed many radios, just never messed with an audi electrically

 

hmm...in my 2001 A4, the factory radio switches on and off when I start and shut down my car. If I turn the radio off when the car is still on, the radio will not turn on the next time I start my car. I can also turn the radio on and off without the key in the ignition.

On the wiring harness I have, there are seperate wires for constant and switched power. That means that Audi has both in their radios. I don't know what the factory colors are, but on my wiring harness red is switched power and yellow is constant power. Still waiting for my Metra mounting kit to come in the mail........