how can i fix ecu unit ford focus?

is your dashboard lighting up as normal, could be the battery??? ECU are not cheap and you wont be able to fix it yourself as it will need re-programming, the ECU is the important part of the car as its main job is too send the right amount of air/fuel mixture, ignition timing etc...you can replace the ECU unit (make sure it for the correct type of car) or send it off to be re-programmed. but first check all wires are connected properly, disconnect the battery for about 30 mins (that will reset the ECU no damage will be done as ECU learn your driving techniques as it did with my 98 mondeo) insure the battery is fully charged then try starting her up.

keith
March 2011