I have a 2002 A6 C5 Avant, which is starting to show it's age, although it stills runs very well.

Latest issue is a whine from somewhere in the climate control system. It is on all the time the engine is running. It ceases when the system is switched off and I can hear it slowing down and stopping after the engine is switched off. It is not the blower, as that works fine and the noise doesn't change with the change in speed of the blower. It doesn't change with engine speed. The noise seems to be coming from the bulkhead on the drivers side.

From the clues it would seem to be an electrically driven motor of some kind, not a belt driven one.

Anyone have any clues as to what it might be?

Big Bruce