If the chassis is non-PATS and keys are not chipped.... Random thought.... Dealer installed alarm? All my Fords have come with one of those dealer installed KARR alarm type systems. If you don't want it, they just "deactivate" it, but it is still there, and can cause problems. I was doing some electrical repair to my 2001 focus, which had one installed way back when but never used, and after 12 years it activated. I could not start the car, and had no way to do anything with the system. I had to completely remove the KARR module and reconnect the start relay wire. Not too difficult but very anoying. There was one on my old 95 Ranger that did something similar. Now the one on our 07 Expy is malfunctioning. I hate these things. This is not likely your problem, but what the heck :)
