Mysterious whirring
 

Hi guys. I need some help. My 2000 V70 is making a loud whirring noise. It sounds like a fuel pump, starts when the electrical system is engaged (half-turn of the key) persists when the engine runs, and stops as soon as the electrical system is turned off. It seems to be coming from the battery or driver's side headlight, which I know is impossible.

Can anyone suggest a possible culprit?

Rick