Wiper motor failure
The wiper motor located beneath the cowling (the plastic cover underneath the windshield is responsible for powering the wiper blades. If this motor fails, it will prevent the wiper blades from moving.
Wiper transmission failure
The wiper motor transfers its power to the wiper blades via a series of gears known as the wiper transmission. If this transmission is faulty, it could prevent the wiper blades from moving.
Windshield wiper linkage disconnected
The windshield wiper linkage is a mechanism that connects the wiper motor to the wiper blades. If this linkage is disconnected, it will prevent the wiper blades from moving.
Faulty wiper switch
The wiper switch controls the operation of the windshield wipers. If this switch fails, it can prevent the wiper blades from working.
Windshield wiper arms and blades damaged
Damaged windshield wiper arms or blades can prevent the wipers from moving effectively.