hi i have a focus zetec 52 plate key fob dosent open doors?

you have to reprogramme key agin by closing all doors fasten front seat belts put key in ignition and turn on and off 4 times in 6 secs you will hear a noise sound and immobilizer light stay on remove key then immediately press unlock or lock button and hold it for 30 secs to programe it then turn ignition back on to accept key and done

here to help
April 2011