the ice maker has completely stopped producing ice
Check to see whether the ice maker has been turned off. Here's how to check. Look for a wire along the right side of the ice maker that looks a bit like a coat hanger. If this wire is in the raised position, the ice maker is turned off. On some units you simply lower the wire to the down position to turn the ice maker on. On others, you lower a small red plastic lever to lower the wire. If the wire is in the proper position check the freezer temperature, it should be between 0-8 degrees Fahranheit. If it is warmer than 10-12 degrees, the ice maker may not produce any ice. Check your door seals and thermostat, repair/replace as necessary.
and if the ice maker is producing ice poorly
When an ice maker is producing ice poorly--when it produces just a few cubes or none, or when the cubes are too small--it's usually because of a clogged water line or a defective water inlet valve.
First, check the water line attached to the back of the refrigerator for good water flow. To do that, first turn off the water supply valve. Then remove the water line from the back of the refrigerator. Next, place the water line into a bucket and momentarily turn the water valve back on to test the flow. If the flow is poor, you need to repair, clean, or replace the tubing or the shut-off valve that supplies the water. If the flow is good, you may have to replace the water inlet valve.
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