Thanks @VBLUE42. I've looked it over a few times and not sure there is anything to screw up unless I'm missing some other wiring. Should this bypass also disable the GPS from knowing I'm in motion?
Like I said, it works perfectly when the GPS Nav cable is removed from the unit, so I know the parking e-brake bypass is wired correctly.
Does the Pink "car speed signal input" need to be wired to anything?