Most likely problem is the motor. To check the switch unplug the motor and hook up an electrical tester to the wiring going to it then turn on the wipers and see if you have any power. The transmission could have snapped (the transmission is basically a rod connecting the motor side wiper to the other), if you can move the one wiper by hand it would most likely be the
trans. Turn on the wipers and give them a little encouragement by hand, if they slowly go your motor is about dead. If they move freely by hand the gears on the motor where it connects to the gear on the
trans could be stripped, are stripped if the motor is running but nothing is moving. Firmly locked in place, dead motor.
wipers quit working 
