The ice maker is turned off or believes the bin is full. It sounds too simple, but it is a regular finding. A wire shutoff arm lifted by a bag in the freezer, an ice-off setting changed while wiping the display, a control lock, or an optical bin sensor blocked by frost or a misplaced bucket all stop production with nothing broken. On in-door designs, a bucket that isn’t seated fully can do the same. Checking these takes a minute: arm down, switch on, bucket seated, sensor windows wiped. Then allow several hours to see whether a harvest follows.
The freezer is too warm. Ice makers wait for the mold to reach a set temperature well below freezing before they harvest. A freezer sitting at 10°F or 15°F may keep food frozen but will produce ice slowly or not at all. If the ice maker was fine until the freezer started drifting, the ice maker is only the messenger, and the real repair is a fan, defrost part or condenser problem. With in-door ice makers the same logic applies to the ice compartment: a failed compartment fan or iced duct leaves the mold too warm even when the freezer itself is cold.
Water isn’t arriving, or not enough of it. A partly closed shutoff, a self-piercing saddle valve that has scaled up, a kinked line, a clogged filter or low household pressure all reduce the volume the inlet valve delivers in its timed fill. Small, hollow or thin cubes are the typical sign. Worse, the slow trickle at the end of each fill freezes in the fill tube, and after a few cycles the tube is blocked completely. Clearing the tube restores ice briefly, but it will refreeze unless the flow problem behind it is fixed.
The inlet valve has failed. The ice maker side of the valve is a solenoid coil and a small rubber diaphragm. The coil can go open, which is easy to confirm with a meter, or the diaphragm can stick so the valve delivers too little water or drips constantly. Scale on the inlet screen reduces flow the same way a clogged filter does. When the dispenser works but the ice maker gets no water, a dual valve with one failed coil is a strong suspect. Replacing a valve is a moderate repair at the back of the refrigerator, and common valves are carried on the van.
Finally, the ice maker itself. Modules and motors wear, mold heaters fail so cubes stick, ejector arms break, twist trays crack, and electronic ice makers lose a thermistor or control. A test cycle, started with a button or test terminals depending on the design, shows quickly whether the unit rotates, calls for water and harvests. Most failed ice makers are replaced as a complete assembly because that is faster and more reliable than rebuilding one. On in-door units the auger motor and chute flap are checked separately, since ice can be made perfectly and still never reach the glass.
