Do a search on the Prestigious Society Nav bypass.
It has nothing to do with the brakes. If you want to watch a DVD then you need to fool the car into thinking it is stationary. That is why the PS bypass does. It tells the GPS that the car is stopped. I love mine, not so I can watch a DVD but to unlock all the nav/radio/phone features that IMHO should not be locked out.
Starlight Black Mica with Ultra Premium II
Total LED change over, clear bra wrap, Prestigious Society Nav Mod and Viper Smart Start and body side moldings.
i believe it grounds off either the parking brake or the transmission in park. you have to find the wire that sends a ground to the dvd player, and connect them both together i saw a write up on this somehwere.