I've had some problems with mine, due to poor contacts in the three relays that operate the motor. I fixed that by removing the relay case covers and cleaning the contacts with some fine grade paper.
That's not your problem, but I took a good look at my wiper system trying to figure out why it wouldn't work.
Firstly, I hope you have all the linkages and bell crank piece for the motor, you just don't have the motor?
Flying Spares in the UK (www.flyingspares.com
) will have a good 2nd hand or refurbished unit for £185.
Ebay could supply for less maybe.
However, if you are a bit handy, you could modify a BOSCH motor from a Mk4 Golf (or new beetle). You would need to cut the ground link on the park switch on the outside of the motor (see photo). That is the easy part as I have done that in order to use the motor on another car.
Now for the bit I haven't needed to do, but certainly will if I have a problem with mymotor as I think £35 fof a new (aftermarket not genuine VW) Golf motor from Ebay is more like what I would want to pay.
You would then need to pull off the tape around the motor body that covers up the brushes.
You need to disconnect the grounded brush from the motor body ground and connect a wire to it and bring that up and out through the cable gland at the top where the red and blue wires come from the other two brushes. In the worst case you would need to undo the two screws holding the motor cover/motor permanent magnets in place for better access to the brushes. You could then undo one of the gearbox screws around the top and put a ring connector on that to provide a good case ground lead.
You would then have all the cables/connections (7) necessary to connect into the RR loom, by following the RR wiring diagram, though you would need to wire up the connections individually as you would not have the original motors multi-plug (not having the motor of course). The small connections allready fitted into the Golf motor's multi-plug connection you can see in the photo are easily connected to by small blade (spade) connectors that can usually be found for car audio speakers and can be readily purchased from car audio/motor accessory suppliers.
Below is my finished motor (for another application remember!), but you can see how neatly it can be modified to fit a different application.
Note I did have another Golf motor (2nd hand) that was faulty. I'll see if I can find it and see how easy/if its possible to modify the third brush connection to pull the ground out for external connection.