The ice maker was overproducing ice for a few weeks. Then it stopped producing ice all together. The reservoir fills up but no ice goes to the evaporator plate. I just replaced the circuit board to correct the overproduction problem. Hoped this would also fix the non-producing problem but no such luck. The unit is cold, water runs, grid gets warm. Just no water running to the plate to make ice. Is it for sure the pump or could it be something else?