Windshield wipers may stop working due to a mechanical problem such as a broken linkage, loose joint or corroded shaft, or an electrical problem such as a blown fuse. If the wipers can be moved easily manually, the problem is most likely mechanical. If not, the problem is probably electrical.
Windshield wipers have many linkages and moving joints that can break or corrode and prevent the blades from moving even if the motor is still working. The windshield wiper motor is constantly rotating, but it can stop if the wiper motor fuse blows. A blown fuse usually indicates an underlying electrical fault such as a short circuit in the wiper-motor armature or faulty wiring, or even a persistent mechanical problem such as a seized bushing.