ok so im having an audio problem, i just hooked up a new stereo system and i have no rear sound. after a while of looking at everything following wires and matching colors. i found that the wiring harness i have is only the 2 pulg one and the rear speakers are on a different plug. now what i was wondering if theres a way i can some how rig it so i can use my rear speakers, or do i need another harness, if i do, which one. thanks

i got an 99 Audi A4 Quattro with the Concert audio now replaced with aftermarket

 

bump?

 

I had this when I fitted an Alpine to my A6. If you have the same factory fitted audio system you'll find a Bose amplifier in the right hand compartment in the boot. It gets it's power from the factory fit stereo so without it the amp gets no power and therefore no rear audio. You can buy an adaptor that provides power to the Bose amp following an aftermarket stereo fit. I wasn't happy with it as I kept getting load thudding noises with every button push on the new stereo (wasn't the stereo as a sony system did the same). In the end I traced the speaker cables from the stereo the Bose amp and then to the rear speakers and unpluged them at the amp and ran a bypass.

Hope this helps.