If the motor runs, and the wipers dont respond, then its probably the linkage. But there are little mechicnial gears and cams inside the wiper motor, they could've sheared apart or similar.
If you can detach the motor and verify the output shaft spins (when on, if it free spins its junk), then the linkage is bad. However with the motor still removed, if you move the linkage the wipers should move, and the motor is failing under load.
1-4 is self explainator, 5 is the linkage, 6 is the motor/regulator. 7-11 are the washer tank.