Did you have to jump the car or possibly have it on (not running, but accessories on) for an extended period of time that could have drained the car battery? I know on some other makes (range rover for example) when the voltage is too low for the car to start the key has to be added back before the car will start. Keeping with the range rover example, on those, when you jump start them, you have to hold the fob against the steering column (the position is indicated by 3 protrusions in the plastic on the bottom of the steering column) and then push the button to start.. Maybe on our cars you could try holding it against the flat part on the side of the steering column (round area where a regular fiesta would have a key cylinder and where you hold it when setting up the mykey stuff) and pushing the button? Not a sure fire fix, but would definitely be worth trying if you havent already.