I have a 2004 350zr with Bose. Using metra harness to install boss bv8974b stereo. I have about no I idea where to put the blue and white one saying amp turn on. The boss has a ground cable but so does the metra (ground b-) do I connect them together? The stereo turns on and reacts me playing my music over Bluetooth but will not play any sound. Any one know what could be the problem?

 

You need to connect the blue amp turn on wire to the amp turn on lead to the factory bose amp in the rear. Or you need to bypass the amp in the back if your running aftermarket speakers. The head unit does not power the speakers in the factory bose system.