Hi Chris, if the warning light does'nt come on when you first switch the ignition "on" then the alterator is faulty, go back to where you got the replacement from and do'nt leave untill you get a working unit!! and get them to prove that it is putting out the correct voltage 14.4v with all electrics on (headlights full beam, rear screen heater, heater fan,)
nigel, April 2008