Marvel Ice Maker Error Code 4 flashes

Four flashes on a Marvel ice maker indicates that both the bin thermistor and the evaporator thermistor are reading as either open circuit or short circuit at the same time. The control board uses these sensors to manage the freeze and harvest cycles, and when both fail simultaneously, the unit stops operating to prevent damage. This error requires testing both sensors with a multimeter to determine whether the sensors, wiring, or control board is at fault.

No, you should not attempt to use the ice maker while it is displaying the 4-flash error. The unit has halted operation because it cannot monitor ice bin levels or evaporator temperatures accurately. Running the machine without functional sensors could result in component damage or improper ice production.

A reset may temporarily clear the error code and allow the unit to restart, but if either thermistor or the associated wiring is actually faulty, the 4-flash code will return once the control board attempts to read the sensors again during normal operation. Resetting without addressing the underlying cause is not a fix and should only be used as part of the diagnostic process to confirm the fault is active and repeatable.

A knowledgeable DIYer comfortable using a multimeter can perform the initial diagnostic by ohming both the bin and evaporator thermistors to check their resistance values. If a single thermistor has clearly failed open or shorted, replacing it is a straightforward repair. However, if the wiring harness or control board is involved, the repair becomes more complex and may be better suited for a qualified appliance technician.

Repair costs vary depending on the root cause. Replacing a single thermistor sensor typically ranges from roughly $50 to $150 for parts and labor combined. Wiring harness repairs or connector replacements may fall in a similar range, while control board replacement is typically the most expensive option, often ranging from $200 to $500 or more depending on parts availability and labor rates in your area.