Unplug the KitchenAid refrigerator's power cord from the wall outlet.
Pull the ice bucket from the inside of the freezer compartment. It will slide out without resistance.
Remove the screws from the front cover of the KitchenAid's ice bucket using a 1/4-inch hex screwdriver, then slide the front cover off. This reveals the drum.
Use your 1/4-inch hex screwdriver to remove the two screws on each side of the KitchenAid's drum. Two screws are on the inside and two screws are on the outside of the drum.
Flip the KitchenAid's bucket over to access the screw on the drum's underside that holds the actuator arm in place. Remove this screw with your hex screwdriver and lift off the arm.
Pull the now loose housing off the KitchenAid's drum to access the drive cam shaft.
Use a flathead screwdriver to remove the E-ring on the end of the KitchenAid's cam shaft by working the tip of the flathead screwdriver under the edge of the E-ring. This will pry it off the shaft.
Slide off the washer behind the E-ring, then rotate the nut behind the washer counterclockwise in order to loosen it and slide it off the shaft.
Twist the drive cam shaft's plastic coupling counterclockwise now that you have access to it. Slide it off the end of the KitchenAid's drive cam.
Put the replacement coupling onto the cam shaft and work it into position, twisting it clockwise.
Follow your procedure in reverse to reinstall the other aspects of the KitchenAid's ice bin.
Slide the bin back into the freezer compartment and plug the KitchenAid refrigerator's power cord back into the power outlet.