i have fiesta , and i have rev counter goes round when i start it?

Eather a drain or the altanator has falt,get a multy meater and test charging rate with enjin running should be 13.20 _14.00 volts,or a12 volt test light,disconect battry earth lead place the test light between the earth lead and earth post of battry it should not be lit,oh turn every thing off including ignition best open drivers window also,if is lit up bright just pull one fuse out and place it back if made no diffrence do the next one,also try disconecting altanater as this also could cause drain on battry

Steven,s
June 2012