I'm getting ready to put the head unit I bought while down range in my truck. Before it got jacked I had an AvicD3 that was hooked up when I bought it. I'm not sure what this pink wire was hooked up to if at all.

I'm thinking vehicle speed sensor or back up camera.

 

You are correct, the pink wire is for the speed sensor or VSS

 

Thanks now to figure out where the reverse signal was wired into.