Hi, I am John Mc, a Ford dealer tech. I hope I can help you quickly and accurately. One moment while I work on your problem.
So you are trying to start the car with the proper key but the theft light is flashing, correct?
Did you do anything that you think could have caused this, battery replacement, used the wrong key... something like that?
not that i'm aware
Ok, then. If your theft light is flashing you probably have a problem where something has lost memory or there is a problem with your pats transceiver. There really is nothing you can do at home. You need to get the truck to a dealer so they can scan the system and find the problem for sure. Unfortunately this is pretty much a dealer only job. Only the dealers have the equipment and software to work on the security systems.
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