Parking brake wire on Kenwood DDX8019

Pull up the parking brake. If you want to bypass that necessity, you need to ground the parking brake wire.

yes just what MObermeier said.

You need to hook up the parking brake wire either to the parking brake switch or to a ground.
If you hook it up to the parking brake, the only way you can watch videos is if the parking brake is on. If you hook it up to a ground then you can watch videos all the time, but it is a danger then to others and yourself since you can watch videos while you drive. I also believe it is illegal to have a video playing in the drivers view in most states.