A friend of mine has just naught the other S that's up here and last night when he switched it off he heard a whirring noise from over his shoulder and this morning the battery was totally flat.
Any ideas?

Cheers Richard

 

Behind you there are roof motors and fuel pump really. The evap system makes a sort of whirring noise iirc.

Did the noise stop?

 

I had a hire Renault Scenic that made a faint whirring noise for long periods after you turned the engine off. It turned out to be a fault with the central locking that drained the battery. Might be worth checking that the car is locked when you press the fob.

 

Fuel pump is the only thing really, over the left shoulder.

The EVAP is more like a cow quietly mooing when parked and everything is hot.

No idea why it would run on though. Did he lock it with the keyfob?

 

Just let everyone know its back up and running again and it hasn't happened again yet.
The whirring noise was straight after turning off the ignition and before he locked it so god only knows what it was.
Thank you for the replies we will keep an eye and ear out for it again.