I have a Ford Focus TDI Zetec 1.6 it only has 28000 on the clock and is 5 years old, I got in it to go to work this morning when I noticed the Battery light was on while driving and everytime i pressed on the accelerator I could hear a gentle whirrin sound. I phoned a garage and they said it could be the alternator but would like to see if anyone else is familiar with this problem. Any help would really be appreciated