had exactly the same thing happen the other day.

Basically the motor arm had detached itself from the wiper linkage.

I managed to fix it with no parts needed.

All you need to do is: remove the wiper relay

(black box next to the wiper motor), undo the bolts to secure the wiper motor, then once the motor is loose and you can see the motor arm through the hole you need to reattach the earth and wiper relay so that you can operate the motor.

Turn the wipers on as usual but turn the ignition off before the wipers would normally finish a full sweep.

You need to do this in order to get the motor off the car.

Even when the arm is in this position it is a somewhat fiddly job to remove it.

There is a plastic bush on the wiper linkage that connects to the motor arm mine was slightly damaged however i pieced it together and pushed the motor arm into the linkage and refitted the motor this is also very fiddly.

It worked and has continued to work for me however the best option is to buy a new bush thing for the wiper linkage if it is damaged as there may be a chance that is could pop off easier in the future.
