Hiya, been away for a while - sorry!
Right, the main fuse for the fan is the 40amp one (yes, 40 amp) as shown in the diagram attached yesterday.
It is not accessible from the fuse panel flap, but requires the removal of the lower dash trim.
To do this, pull sharply backwards (ie towards the rear of the car) on the top edge of the trim panel. There are 2 securing clips on the door side of the steering wheel and 1 clip on the passenger side.
Once off, you can fold down the trim panel, it's quite flexible and then remove the fuse, next to the relays as shown.
Once this is done, it will disable the fan.
However, you need to get a diagnostic scan done on the car to see what the faults are, before rushing out and buying any parts. The dealer is the best port of call for this really, unless you know someone with a full version of VAG com.
Cheers,
Mike