It could be that an internal breaker contact is not being made when the juicers arm is snapped into place for use. If you dont hear a "click", its probably the breaker contact that needs adjusting. Remove the bottom cover, and look for the contact below one of the arms internal spring hinges. Try loosening the single screw of the breaker contact base to see if the breaker makes contact with the arms hinge. You should hear a "click". If you still don't, you have to unscrew the contact base completely and"rebuild" the seat of the base with a piece of foam or tape, re-screw in place, and try again until the breaker makes contact with the arms hinge.