I just bought a 1998 A6 that has all of the usual electronic gremlins (battery drain, LCD cluster problems, bad gas gauge, etc), and on top of it all the previous owner did something weird with the Bose system.

I'm posting some pics here and I'll have a link to a youtube video. Basically I want to get everything rewired back to normal so I can use the stock stuff. Even if the speakers are bad, i can replace them but as it is this wiring is all jacked up.











I found this for a speaker wire color diagram:
2000 Audi A6 Car Radio Stereo Audio Wiring Diagram

here's a little video I shot:

1998 Audi A6 Bose Stereo problem - YouTube


Any help you can give me would be greatly appreciated.

Mostly, here's what I need to know - what color wires do i need to reconnect and what do I need to get rid of? I can solder and string wire through. I know what RCA is. I know how to get the right gauge wire, etc. I've installed stereos before...I've just never done subs nor have I seen all this macguyvering. There is a sub power cord that was attached to the battery. That was done pretty well, but I don't intend on doing an aftermarket sub so I'll be pulling it.

 

I figured out that the wiring diagram I have is wrong. The colors aren't correct.

Does anyone have a link to the correct wiring diagram?

 

I might have found a wiring diagram...but this thing is so jacked up, it's annoying.

I got a metra wiring harness - 70-1787

It says for: 1996-08 Audi A4 / 1998-04 Audi A6 (and then a few other models)

The problem I'm having is that he red plug and black plug do not have wires that line up with the plugs I'm supposed to plug them into (the yellow/blue/green plug, the other red one and black one)

Also, I should mention I'm putting in a Kenwood KDC 255U. This only has a rear/sub rca output.

 

Here's my update for anyone else who's reading this.

I found out where almost all the wires go. I reconnected the stock plug and got rid of all excess wires (sub power, extra speaker wire, etc).

But now I have 4 wires coming out of the back of the amp and I have no idea where they go. Can you look at the pic and tell me?

This is my fix of the connector:




Here are the wires in question - you can see their position in the back of the amp. they are black, white, blue with yellow, and green with yellow




Here are the wires up close:




Here's the empty space where the amp and sub go. I don't see any other wires coming out that these need to hook up to

 

I think I just figured it out. There's a little female 4 prong plug on the back of the amp (where those wires come out). I traced those wires to the sub itself. So, I'm guessing these are power and sound input wires and they are supposed to plug in to the little 4 prong plug.

Can anyone confirm?

 

I confirmed that I need to get those wires plugged into the white plug.

Can anyone tell me which wire goes where? i.e. black top left, white top right, etc.

 

HI, did you use multimeter and resistance measuring to know where wires go or how you did it?
As for 4 pins i think you have ground , signal in , amplified output and +12V.
You could measure resistence between 4 wires and around 30-60Kohm could be signal in.
Signal in also has to use ground so if you find 1 more with higher resistance it could be cable to speaker as closed transistors should have high resistance.
But also power in might have high resistance so it might be quite hard to know unless you have schematics but maybe if you open amplifier and post it to some electronic forum people will know where power goes where signal goes etc.
Are there even schematic avalible for oem sound systems?

 

I found a schematic - but only for the main brown plug (pictured a few replies up).

This cable goes from the back of the amp to the two woofers in the unit. Because two wires are colored (blue with a stripe), and one wire is black and one wire is white, I'm assuming black is ground, white is hot, and the blue wires are speaker wires.

However, I don't which corner of the plug they attach to. If someone has the Bose system and can go look at their unit and tell me which one goes where, that would be awesome. All I need to know is does black go top left or bottom right? that sort of thing.