Hi!
I had the same problem with a customer 2 weeks ago. The radio comes from the factory with an anti-theft code. Every time you run out of power to the car, for one reason or another, the radio will lock up and ask for that code. If the radio is original to your car, I will explain how to get that code:
1. try looking in the car's papers.
2.Go to the Ford dealership (I don't recommend, the customer asked 35$ for the unlock).
3. Apply the same method I used. You have to take the radio off, and on the radio you will find a label with a serial number. You can find a lot of websites on the net that offer radio unlocking services, I got it from here : ford radio code, or you can try on ebay.
Good luck! :)
