based on the Hyness Work Manual, if you have changed your battery (or disconnected it ), some vehicles (for example, Ford) need to be calibrated：
by turning your ignition on putting your tran in drive with your foot flat on the brake peddle and hold for 3 minutes and then turn ignition off and then back on with the car in park and no peddle , do not start car to do this just ignition on !
then, everything should be ok.
