Why a Whirlpool ice maker is diagnosed by symptom
The automatic ice maker built into a Whirlpool refrigerator or freezer is a module rather than a standalone appliance, so it has no error codes of its own. Any PO, HI or LO message you see belongs to the refrigerator’s display, not the icemaker. The icemaker itself is read by what it does — no ice, slow ice, small or hollow cubes, or leaks — so the symptom is the diagnostic.
No-ice and slow-ice symptoms
No ice at all usually traces to a closed or kinked water supply, a clogged EveryDrop™ filter, a frozen fill tube, a failed inlet valve or a failed harvest motor or module. Slow or undersized ice points at low water pressure, a partly clogged filter or a partly failed inlet valve. Cubes that fuse together in the bin point at a low ambient temperature, a stuck motor or a control that is not cycling. A unit that runs but the tray stays dry points at the inlet valve or the supply line.
Leak and what-to-do symptoms
Water on the floor or in the bin usually traces to a loose supply-line connection, a continuously dripping inlet valve or a frozen-then-thawed fill tube. Replace the water filter, confirm the supply shutoff is fully open and check the fill tube for ice before suspecting a part. If the icemaker still will not produce, runs slow or leaks, an experienced, independent technician should diagnose the inlet valve, fill tube, module or motor with the correct genuine OEM part — this work is handled as part of refrigerator repair or, for an undercounter unit, ice machine repair. Browse the symptom guides on the ice maker diagnostics page.