I have a 1/2 hp Craftsman chain drive opener that just buzzes when I press the wall mounted switch. I have a flashing green LED on the back, and pressing the reset button doesn't help any. Door will open freely when I unlatch the trolley. Any ideas?
Does it buzz momentarily, or does it continue to buzz until you press the button again? Also, a model number may help. In the mean time though, I would check the plastic drive gear on the top of the unit, to see if it is worn; it is intended to strip, break, whatever, rather than burning out the motor or other component, in the event that the door became jammed or otherwise inoperative.