How important is the VSS wire? If I don't hook this up on my in-dash gps will it be off by a few feet only?

 

I would guess its not that important, although I do not have a indash gps, nor have I installed one, but I have gps system and it is pretty accurate and can guess the speed accurately and isnt hooked up to the vss.

 

I'm pretty sure the GPS uses your coordinates to determine your speed.

 

I'm pretty sure that is just for the unit to know if your moving or not to lock out certain features. So instead of a parking brake, it makes sure your not moving. GPS speeds are accurate to 0.1mph if I remember correctly.

EDIT: I'd like to emphasize that once your going over say 5mph or so GPS speeds are very accurate, only at very slow speeds does the accuracy diminish.

 

OK thanks guys.