DIAGNOSIS The machine has hit its programmed cleaning reminder interval (usually after 24-48 hours of cumulative operation). It will lock out normal function until you run a clean cycle.
FIX This is straightforward. Ensure the water reservoir is filled to the MAX line with clean, cold water. Press and hold the 'Clean' button for 3 seconds. The machine will begin a 15-minute automated cycle. It will pump water and cleaning solution (if added) through the system and drain it. Do not interrupt it. When it finishes, the light will stop flashing.
IF THAT DIDN'T WORK The drain pump might be clogged, preventing the clean cycle from completing. Unplug the unit. Check the drain hose at the back for kinks. You may need to manually clear the drain pump impeller of scale.
HEADS UP Do not ignore this reminder. Scale buildup from minerals in the water will permanently reduce ice production and can clog the water distribution tube over the evaporator.