By "ice maker isn't working" do you mean it isn't filling with water, it isn't freezing the water in the ice maker, it isn't dumping the ice cubes into the bin, or it isn't dispensing ice cubes?
Was it previously working and it is not working now?
Typically one can hear the valve when it opens to fill the ice maker with water. Can you hear it attempting to do so? If so, and there isn't any water in the ice tray, check that there is water supplied to the valve at the wall and the valve is open. Is there a water filter? Has it been replaced per the manufacturer's recommendation? (Typically, the water filter should be replaced every six months.)
Is the "full" bar pushed up? It shouldn't be. The bar above the ice cubes should not be in the horizontal position. That position tells the ice maker the bin is full so it should wait until the bar goes down, indicating some ice has been used.
Can you hear the bayonet turning? Is the ice maker attempting to dump out cubes whether or not they exist? The next issue after you confirm there is water going into the ice maker that is being frozen and the ice maker knows to dump the ice, is the bayonet. There is a motor that turns the bayonet and a mechanical connection. Either could be at fault.