Hi,

I have a 1999 A6 Avant with the factory installed Bose stereo system (non CD-changer version). A previous owner hacked up the system and I'm trying to re-install it, except with an after market head unit as I don't have the original. The harness that goes into the sub enclosure has also been removed so I have wires coming directly from the amp circuit board, and they are incorrectly coloured according to my wiring diagram (I guess they change colour once they leave the missing harness). I have reconnected everything except for three wires, which I cant work out what they do - the wires coming from the circuit board are labeled below:

1. thick red - power
2. medium red - speaker 1
3. medium blue - speaker 1
4. thick black - power
5. thin orange - remote
6. thin red
7. thin yellow
8. thin blue
9. medium yellow - speaker 2
10. medium blue - speaker 2

Anyone have any ideas what these wires do? I have the power, ground and remote working because when I connect the remote the amp makes a clicking noise. My thinking leads me to conclude the three wires must carry the audio signal from the head unit to the amp, as in the wiring diagram they connect the head unit to the amp but no description is given as to why - they are just colour labeled. Could I get them working with the RCA outputs from an aftermarket head unit, or from the speaker outputs?

Many thanks!

P.S. If anyone wants the wiring diagram i can email it over - it wont let me upload it on here as the file size is too big, even after using Acrobat Pro to shrink it!

 

What stereo are you putting in?