My Anti Theft Lock Is Flashing And My 2005 Ford Focus Want Start

The blinking light is the anti-theft light. There is a 'chip' in your key and the anti-theft system in the Focus has to be programmed to recognize the code that chip transmits before it allows the car to start.
For whatever reason, the car is not reading the code that the key is transmitting. This could be due to a faulty key, a faulty antenna loop at the lock cylinder.. or it could even be interference due to another key on the key chain or a device such as a Mobil Speed Pass transmitter.
Try removing your key from the key chain and see if it starts. If not then try another key if you have one.
Past this it has to be diagnosed with a ford-compatible scan tool which means it'll most likely have to visit the dealer, however some locksmiths have been investing in this equipment as well so it may be worth making a few calls. Good luck!

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