Hi, So my 99 A4 has 90K miles on it and continues to cost a boatload to maintain. The latest issue is that the wipers started moving very slowly several weeks ago, and then eventually stopped altogether. If I help the wipers along, then they are able to move some on their own, but not very much before stopping again.

I hope the wipers are something I can actually fix myself, so I started into it this morning. I removed the entire wiper linkage system which seems to work smoothly. The linkage ends are by no means 'frictionless', but they do move smoothly.

I also disconnected the Bosch motor to see if it was dead. The motor seems to work when I connect it to a 12V DC transformer, so I think it's in good shape.

My best guess is that the wiper control module is shot. Here's why:

The motor has a 5-pin connector on it to connect to its control module. Between the 5-pin connector and the motor itself are only two wires that power the motor (green / red; probably common / +). The interesting thing is that even when the engine is running and the wipers are turned on, the two contacts from the control module wiring that align with the wires that actually power the motor have zero voltage across them. Also, the voltage across one of the contacts that aligns with one of the motors' wires and one of the contacts that does not align with anything reads 14 volts.

So if the linkage and the motor seem to work, and the voltage driving the motor is zero, then the controller is dead. Any comments on whether this sounds right? If it sounds right, any advice on how easy or difficult it is to change the controller? Is it possible that it's simply a matter of changing the controller on the steering column, or is there some type of in-line integrated circuit that is buried somewhere behind the dashboard? Thanks for the help...I'm really hoping to not throw $500 on this problem!