I bought 07 F250. When I crank truck message appears improper detection of parking brake lead. As I have been reading, you can bypass it. Ok here is the deal, my Nav menu will not work. Cannot access some of other menus. But I am able to watch Dvd going down interstate after pressing ok on menu about being illegal. It all boils down to...is the parking brake bypassed? And second, why cant I access Nav menu and other options? Plz help.