Hi All,

I know this has probably been asked a thousand times, I have just installed a sony stereo in my 02 audi A4 but now the rear speakers dont work. I know this is a common problem but I would like to know whether this is a easy fix? Stereo is a MEX-BT3900U.

Im using the loom that came with the stereo although I had to *******ise it slightly to add both the Yellow and Red cable from the audi to the red going into the Sony.

Help greatly appreciated.

 

its because the wiring harness does not have rear output left and right. it has a signal wire that goes to the rear.

 

Whats a signal wire? what does that mean exactly? Is there anything I can purchase or do to fix this issue?

Thanks for your help.

 

You should have bought a wire harness for the stereo that would have plugged into the cars wiring harness. Try Metra. I just had a 7 inch pioneer stereo, a 500 watt amp, and a 10 inch sub installed in my car. I have the Bose stereo, and I needed to buy something so it would work with the factory amp. I completely forgot. I'll have to check the receipts.