Hey guys, removed the factory radio and installed an alpine head unit using a harness adaptor that connects only to the black and brown connectors in the dash. The other two connectors (tri color and red I think?) are not connected to anything. From what I've read it seems as though there is an amp that powers the rear speakers and the connectors I'm using do not connect the aftermarket stereo to it so that's why only the front speakers work. My question is what do I need to do to get the amp powering the rear speakers to get a signal and get the rear speakers to work? I tried connecting the blue/white remote turn on wire from my head unit to all the wires on the two unused plugs but nothing happened. If anyone has a simple solution please let me know.

 

I'm assuming you don't have the Bose system, correct?

 

dont know if this helps but i bought mine with aftermarket stereo and when ta is of my rear speakers dont work

 

correct, not the bose system

 

Here is a post that should help. Ask if you have specific questions.

https://www.audiforums.com/forum/b5-...hookup-196357/

Doug

 

I had to rewire to get my back speakers to work. I believe the preamp was the issue.