The wiper linkage has probably popped off the arm on the motor. There is a plastic bushing that holds the linkage on and they wear out and then it falls off.
To check it you remove the wiper arms and then the cowl panel cover between the hood and the windshield. If that's what happened you'll have to get wiper linkage at your dealer or a wreckinng yard. Ford doesn't sell the bushings seperately.