I got my 7600 installed In my tahoe and love it so far. This is my first pioneer unit.
I stumbled upon a video bypass. After installing the parking brake bypass and connecting the gps antenna, I connected the speed wire to what I thought was a vss wire going into the old onstar box. It wasn't the correct wire, however it delivered a pulse to the unit that made it think I was only going 1 mph. Idk what the wire is but it means all we need is a signal to the unit so its tricked into seeing the wire connected but not detecting a speed.
This allowed video and nav to work at the