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Error code reference

Whirlpool Ice Maker Error Code On/Off LED and Max Ice LED blinking

Harvest failure

Whirlpool codesWhirlpool ice maker codes

Harvest failure — evaporator thermistor may be disconnected, open, shorted, or sealed system issue (low refrigerant, restriction in gas loop, or faulty hot gas valve).

First step from the service manual

Check that the evaporator thermistor is connected to the sealed system tubing and fully connected to the control box. Check the resistance of the thermistor. If thermistor checks good, look for a frost pattern on the evaporator plate.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

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  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
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What On/Off LED and Max Ice LED blinking means on a Whirlpool ice maker

When both the On/Off LED and Max Ice LED blink simultaneously on a Whirlpool ice maker, the control board is signaling a harvest failure. The harvest cycle is the process by which the evaporator plate warms slightly, allowing formed ice cubes to release and drop into the storage bin. This cycle depends on the evaporator thermistor accurately reporting temperature to the control board. If the thermistor is disconnected, reads an open circuit, or is shorted, the board cannot confirm that the harvest cycle completed successfully, and the blinking LED fault is triggered.

The evaporator thermistor must be physically secured to the sealed system tubing and fully plugged into the control box connector. A loose or corroded connection can produce intermittent resistance readings that mimic a faulty component. When diagnosing this fault, check the thermistor resistance value against the specification for the current temperature. A thermistor that reads outside the expected range at a known temperature is faulty and requires replacement.

If the thermistor checks out electrically, the fault likely originates in the sealed refrigeration system. Low refrigerant charge, a restriction in the gas loop, or a faulty hot gas valve can all prevent the evaporator plate from reaching the temperature needed to release ice. In these cases, inspect the evaporator plate for an abnormal frost pattern, which can indicate where a restriction or refrigerant issue is affecting heat transfer. Sealed system repairs require EPA 608 certification and specialized equipment.

Source: manufacturer service documentation.

Common causes of On/Off LED and Max Ice LED blinking

  1. 01

    Disconnected or loose evaporator thermistor

    Wiring / connection

    The thermistor connector may have come loose from the control box or the probe may have shifted away from its mounting point on the sealed system tubing. A visual inspection of the wiring harness and connector at the control box is the first step.

  2. 02

    Faulty evaporator thermistor

    Part replacement

    If the thermistor is physically connected but reads outside the expected resistance range for the ambient temperature, the sensor itself has failed open or shorted. A defective thermistor must be replaced for the control board to properly monitor harvest cycles.

  3. 03

    Faulty hot gas valve

    Part replacement

    The hot gas valve diverts warm refrigerant gas to the evaporator plate during harvest to warm it and release the ice. If this valve fails to open or does not open fully, the plate never warms sufficiently and the harvest cycle times out.

  4. 04

    Low refrigerant charge

    Part replacement

    A refrigerant leak reduces the system's ability to both freeze water during the freeze cycle and warm the evaporator during harvest. An abnormal or uneven frost pattern on the evaporator plate is a common indicator of low refrigerant.

  5. 05

    Restriction in the refrigerant loop

    Part replacement

    A blockage in the sealed system, such as a clogged filter drier or a kinked line, can disrupt refrigerant flow during the harvest cycle. This also typically produces an abnormal frost pattern and requires sealed system diagnosis by a certified technician.

See the test procedure for each cause

Frequently asked questions about On/Off LED and Max Ice LED blinking

What does On/Off LED and Max Ice LED blinking mean on a Whirlpool ice maker?
When both the On/Off LED and the Max Ice LED blink at the same time, the ice maker is signaling a harvest failure. This means the unit attempted to drop a batch of ice but could not confirm the cycle completed. The fault typically points to the evaporator thermistor or the sealed refrigeration system, including the hot gas valve or refrigerant charge.
How do I fix the blinking On/Off and Max Ice LEDs on my Whirlpool ice maker?
Start by checking that the evaporator thermistor is firmly attached to the sealed system tubing and that its connector is fully seated in the control box. Test the thermistor resistance and compare it to the expected value for the current temperature. If the thermistor checks good, inspect the evaporator plate for an unusual frost pattern, which can indicate a refrigerant or hot gas valve issue that will require a certified technician to address.
Will resetting the Whirlpool ice maker clear the blinking LED fault?
A reset may temporarily clear the blinking LED indicators, but if the underlying problem has not been corrected, the fault will return once the unit attempts another harvest cycle. A reset is useful for confirming whether the fault is intermittent, such as a loose thermistor connection, but it is not a repair. Address the root cause before relying on a reset.
Is it safe to continue using my Whirlpool ice maker while these LEDs are blinking?
The ice maker is not producing ice properly while this fault is active, so continued use will not yield usable output. There is no immediate safety hazard to the home from the blinking fault itself, but running the unit repeatedly through failed cycles without diagnosis can cause additional wear on components. It is best to diagnose and repair the issue promptly.
How much does it cost to repair a Whirlpool ice maker showing this harvest failure fault?
Repair costs vary depending on the root cause. Replacing an evaporator thermistor is generally a lower-cost repair, typically ranging from around 50 to 150 dollars for parts and labor. Sealed system repairs involving refrigerant recharge, a hot gas valve replacement, or restriction removal are more involved and can range from 200 to 600 dollars or more depending on the technician's rates and the extent of the work needed.

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