Car won't start, theft light flashing

[Pete@FTR]

Last night after work I went to start my car, but when I put the key into the run position the theft light starts blinking really fast. The engine will turn over but then it automatically dies. Any ideas?

 

[Musturd]

Pats system tripped some how . You can get ford to reflash it or what I always do is replace the ignition with a new one and re program the keys myself