Take it to the dealer,Ford's security system is a pain to work and my father has one that is being one,a 2000 Mustang.It sat in his "Barn" during some auto body work done and tried to drive it out one night sending it to the neighbor for paint work to be done.Would not start at all.Ford does lie about their vehicles unstealable with this system.I know one yard can prove,has two Ford trucks stolen and recovered without the keys.