Hi, Larry.

Before replacing the ice maker, you need to make sure the water inlet valve is not faulty. Check if the ice maker fill tube is not frozen. If it is, the inlet valve should be replaced. In case if the fill tube is not frozen, get to the rear of the refrigerator, remove the cover at the bottom and locate the dual water valve. The smaller diameter tube is going to the ice maker. You will have to switch around the electrical plugs on the control coils, most likely you will need to use a zip tie to hold the plug on the red coil. Make sure it's making a good connection. Next, press the water lever at the dispenser for six, seconds, then open the door and check if there is water inside the ice maker. Water comes in - replace the ice maker. No water - replace the water inlet valve.

Here is a breakdown diagrams and parts list for your refrigerator

Model PSS27NGPACC

The water valve Part number: AP3192626