does anyone know where to find a 12V ACC to turn my deck on and off? i have a 2006 a4 and i looked everywhere, including the fuse box inside the car. i also tried looking in the fuse box under the hood but i cant get the cover off. is there anything i can use under there? and if there is, how do i pull the cover off?

 

Well i found the answer to my own question so if anyone else gets stuck at the same point as me here's the solution: pull off the cover under the steering wheel and you will see a black and pink harness with a big red wire, a big black/yellow wire, a small black/yellow wire, and a small brown wire.
The big black/yellow wire is the 12V ACC source but double check with a multimeter to make sure you only have 12V when the car is on.
The harness is plugged into some sort of cube fuse.
Pull the fuse off and then pull the harness off.
Now you gotta strip a piece of shielding off of the big black/yellow wire, unless you can pull the connector out of the harness.(it would make life easier if you could) But if not, then you have to solder or crimp a wire to the bare black/yellow wire.
And after that all you do is route the wire to your deck and cover up the soldered wires and put everything back together.

 

The guys at Future Shop did the install for me

 

I am having the same problem - not being able turn my deck on/off with the ignition....thanks for the info....does this work for an 2003 A4? and what is the black and yellow wire used for?

 

I forget what it's for but I think it's the Ignition. But as far as I know your car shoudn't be a can-bus system so u should have 12V acc sources readily available. Did the factory deck use a 12V acc source to turn on/off?