Help! Engine fan draining battery after cars switched off -

[boombastictiger]

On my 1.8t Passat, after it is switched off one of the fans in the engine bay comes on and off intermittently. This caused the battery to die after a few hours so i called breakdown out and he didn't have a clue what it could be! The engine light was on so he reckoned something to do with this. The fan is not for the radiator and has a loud hiss which comes from near the turbo but seems to be behind some covering so cannot see it.

Does anyone have any ideas what it could be?

Thanks

Sk

[silentbrown]

boombastictiger said:

Does anyone have any ideas what it could be?

Electric water pump on those? Should run for about 10 mins after switching off to cool the Turbo etc.

Probably an oil temp sensor somewhere that's glitching. VAG-COM time...?

[TonyRPH]

That sounds like the secondary air pump to me.

But that should only activate on a cold start, and only run for about 50 seconds or so.

Are you sure it's not running all the time OP?