The water control valve must switch from water dispensing to ice making. It cannot switch if there is not enough water pressure. This could be because the water filter has gotten clogged from regular use causing low water pressure. Refrigerators come with a bypass filter. Use it to swap out your old filter. The icemaker should work now. The bypass filter has no filter media in it. It will never clog. Or, buy a new filter if you prefer. Shop online for a generic filter. Target has a good price for 3.