I installed the unit in my 04 Chevy suburban. I hooked up the VSS wire to the instrument cluster harness. did the mod to move the mute wire one slot over on radio harness and just grounded the parking brake wire.

Problem I have is that it does not seem to have bypassed? It still locks out when the vehicle moves and you cant change anythign on navi or settings. Is it because of the parking brake wire still? shoudl I have hooked it up to theat switch? help

sounds like your mute wire is not done right. either it was moved to the wrong pin, or it is not inserted in far enough.

side note, when you moved the mute wire, did you ground it along with the P-brake wire? or did you just ground the P-brake wire?