concert 2 player in an older A6

Hi,Can anyone help please..I have put a Concert 2 cd player into my 2001 A6 Avant,but also had to install a CAN Bus simulator to operate the ignition & illumination.The problem is,it switches off via the ignition OK,but still no illumination.Any ideas,or where can i obtain a wiring diagram of the radio set up,showing colors many thanks sjfedex