First thing was I had my front bumper off to replace a headlamp so I checked all the hoses that run along the back of the bumper and they were all fine. Checked the hose down from the reservoir while i as at it.
Then checked the fuse (can't remember which one it is but it is a 20 amp, yellow, tells you in the owners manual) and found it blown. Replaced the fuse, tried again and it popped. gave the motor a closer dose of looking at and found it had a crack down the side.
Ordered from local Audi dealer: a new pump (3B7955681), rubber grommet (431955465A, not sure if this is really required but i replaced it anyway, cost pennies!), and last but not least is the electrical connector (1J0973722A, as the original connector and the new pump electrical connections did not match) then fitted em all. the old pump just pulls out and the new one pushes in.
There are two options here, one is to order that last part and replace the connector which I did, or you can gently file of the extra plastic 'spline' on the connection of the new pump so it will fit (obvious when you see them), tbh the conector is fairly easy to fit.
Then was a case of new fuse in, put water in and spray away. that was when i found that the mechanical action of the washer jets moving was a bit sticky and one didn't retract fully so as i said just pulled them out by hand and sprayed WD then gave them a good working in and out.
I also put a load of fairly hot water through the washers,not sure if this actually helped at all but i figured since they had not been in use for so long it wouldn't hurt.
Ross.