the ice basket is full but it won't stop making ice, it just overflows and dumps it into the bottom tray.

Diagnosis

The Crownful Countertop Ice Maker relies on a pair of infrared (IR) sensors located at the mouth of the ice chute to detect when the basket has reached capacity. One sensor emits an IR beam, and the other receives it. When ice piles up and breaks this beam, the machine triggers the "Ice Full" indicator and halts the harvest cycle. If the machine continues to dump ice into an overflowing basket, it means the receiver is not detecting the beam interruption, effectively "blindly" pumping ice. This failure typically occurs due to two specific reasons: mineral scale buildup or "frost fogging." Over time, calcium and magnesium from your water supply create a cloudy, white film over the clear plastic sensor windows. Alternatively, condensation can freeze into a thin layer of ice directly over the sensor lens. In both cases, the IR beam is diffused or blocked from the start, or the sensor becomes insensitive to the ice cubes, causing the logic board to believe the basket is perpetually empty.

How to Fix It

To resolve the sensor failure and restore the automatic shut-off function, follow these precise steps:

1. Disconnect the power cord from the wall outlet and remove the ice basket and the bottom drip tray to clear your workspace.
2. Locate the two small, circular clear plastic windows situated on the interior walls of the ice chute (the area where the ice drops from the freezing pins into the basket).
3. Dampen a high-quality cotton swab with a solution of 50% distilled white vinegar and 50% warm water. Avoid using harsh chemical cleaners or abrasive scrubbers, as scratching the plastic lens will permanently distort the IR beam.
4. Gently scrub the sensor windows in a circular motion to remove mineral deposits. If the buildup is heavy, let the vinegar sit on the lens for 60 seconds before wiping.
5. Use a fresh, dry cotton swab to remove all moisture and residue. Any remaining water droplets can act as a lens, potentially causing the sensor to malfunction again.
6. Ensure the area around the chute is free of any stray ice shards or frozen condensation that may be physically obstructing the sensor's line of sight.
7. Reinsert the basket, plug the unit back in, and test by manually filling the basket with a few handfuls of ice to see if the "Ice Full" light illuminates.

If That Didn't Work

• Check for Ambient Light Interference: These IR sensors can be "blinded" by direct sunlight or high-intensity halogen kitchen lighting. If your machine is placed directly under a bright spotlight or next to a sunny window, the external light can flood the receiver, making it unable to detect the beam break. Try moving the machine 2-3 feet away from the light source or shielding the top of the unit with a temporary cardboard cover to see if the sensor begins working.
• Inspect for Sensor Misalignment: If the machine has been bumped or dropped, the internal sensor brackets may have shifted. Use a flashlight to look into the chute; the two sensors must be perfectly aligned across from one another. If one appears tilted or pushed back into the housing, the beam will never hit the receiver, and the machine will run indefinitely.
• Hard Reset the Control Board: Occasionally, the logic board can hang in a "production loop." Unplug the unit and leave it disconnected for at least 30 minutes. While unplugged, open the lid and let the remaining ice melt slightly to ensure no "ice bridges" are forming around the sensor windows.
• Verify the Ice Basket Fit: Ensure you are using the original Crownful basket. Third-party or modified baskets that sit slightly lower or higher than the factory specifications can sometimes fail to trigger the sensor at the correct height, leading to overflow before the beam is broken.

Heads Up

• Use Filtered Water: To prevent the mineral buildup that blinds the sensors, use bottled or filtered water. Hard water is the primary cause of sensor failure in these machines.
• Weekly Cleaning: Every 7 days, wipe the sensor windows with a damp cloth even if the machine is working. Preventative maintenance prevents the "Ice Full" failure from happening.
• Avoid Overfilling: Do not manually pack the ice basket down to create more room. This can push ice into the sensor housing, potentially cracking the delicate plastic lenses.
• Dry the Exterior: Ensure the top of the machine is kept dry. Water seeping into the top vents can cause short circuits in the sensor wiring, leading to erratic "Ice Full" readings.