Slide the ice tray out, and grab the auger motor and try an twist it. If it doesn't move there is a good chance that it froze up. Try installing this part here
after you use a blow dryer to dry it out. It is a rubber cover that wraps around the back of the motor to keep moisture out. If it does turn when you grab it. Pull the entire thing out, and disconnect it. Trace back the wire's from the motor assy. to the pin connector. Take your meter, set it for ac, and check for power coming to the correct pins when you depress the dispenser pad for ice. If you have power the motor is shot, If you don't have power, your problem lies in the dispenser.