ihave a f 150 last nigt my son tried to start it with the wrong key (KEY FOR THE DOORS ONLY NO CHIP) after a few tries i went out side and it would not even turn over. so i found a spare key today and it started pulled to the top of the drive and turned it off and tried the key that i use most of the time and now niether key will work. no its not a dead battery

 

I dont know how accurate this is, but when i tried to get a "door only" key made, the guy at home depot wouldnt cut the key. He told me putting a non-coded key in the ignition disables the computer and it requires a trip to the dealer to get everything reset. You might want to call your dealer's service dept on this one.