2003 Audi A6 Car Radio Stereo Audio Wiring Diagram Whether your an expert Audi electronics installer or a novice Audi enthusiast with a 2003 Audi A6, a car stereo wiring diagram can save yourself a lot of time. One of the most time consuming tasks with installing an after market car stereo, car radio, car speakers, car amplifier, car navigation or any car electronics is identifying the correct color wires for a 2003 Audi A6. Audi Alarm, Remote Start, and Stereo Wiring - the12volt Disclaimer: * All information on this site ( the12volt ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.