Sony aftermarket radio install issues
So I'm trying to install a XAV-ax1000 Sony aftermarket radio in my excursion. I got the Metra 70-1771 wire harness and when I wired it up there was no audio coming through the system. In addition to the main wire harness that I plugged into the vehicle there is an extra wire harness coming out of the vehicle that was left that you can see in the photo. Not sure what's going on but I'm getting no audio when plugged in. It's a 2005 Ford excursion XLT. I do not have a DVD system in the vehicle. Any idea why there's no audio? I've been told that that secondary plug is for an amp for a rear system but I don't have a DVD audio system at all. The only thing extra in the back is audio controls for the second row on the bottom of the center console.