OK, just saying 'fuse' WAS kinda lame.... :roll:
Following culled from an A2 Bentley and some experience with my A2 power locks:
Electrical:
Drivers door lock has the electrical switch that turns pump on.
The pump has a 3 wire connector on it. you should get 12V between the centre pin and the 2 outer pins. One outer pin is hot with drivers door locked, other outer pin is hot with drivers door unlocked.
If you have a good fuse but no power to pump, I'd get inside the drivers door first and see if all is well with the master activator.
If power to pump but pump doesnt run, maybe bad pump.
Leaks:
The pump uses pressure to open locks, vacuum to close.
The pump should shut off within 5 seconds unless there is a leak. If it runs longer, then try pinching off the hose right by pump, if it shuts off now, work your way through the car pinching off hose a various points until you find the leak Lots of interior dissasembly may be required to get to hoses!. Dont forget the gas flap and trunk hoses.