These units have safety features so you normally will not be able to program the navigation unit or change certain settings while the car is moving. The proper procedure is to stop the car and pull the hand brake. There is a known bypass to disable this annoying feature so you can program the unit when the car is moving. Thanks to the avic411 forum, it is very easy to do.
Take the yellow/black wire from the top row (1st pin) out of the head unit wire harness. It should come out easy when you pull on it but you may have the lift the tab on the connector a bit. The yellow/black wire is the Mute wire but we are not using that wire for anything else.
Insert the yellow/black wire in between the two black wires (4th pin) on the bottom row. You may have to lift the tab on the connector with a small pointy object like a needle.
Ground the yellow/black and the green wire (from the black head unit connector) with the other ground wires on the harness.
The green wire would normally be connected to the hand brake so the unit knows when your car is parked.
