Frigidaire Ice Maker Error Code 4 blinks

The 4-blink code means the control board has detected that both the bin thermistor and the evaporator thermistor are reporting resistance values outside the acceptable range at the same time. In response, the board shuts off all loads including the compressor, fan, and water valve, and the unit stops making ice entirely. The fault must be diagnosed and corrected before the ice maker will resume normal operation.

A reset may temporarily clear the fault display, but the 4-blink code will return immediately if the underlying cause has not been corrected. Because the error triggers a complete shutdown of all loads, the ice maker will not run reliably until both thermistors are confirmed to be within the specified resistance range and all wiring connections are secure.

Repair costs vary depending on which component has failed. Replacing one or both thermistors is generally the least expensive repair, with parts typically ranging from $15 to $60 each plus labor. If the control board is the root cause, parts and labor costs will be higher, commonly in the range of $150 to $350 depending on the specific model and service rates in your area.

Start by testing the resistance of both the bin thermistor and the evaporator thermistor with a multimeter and comparing the readings to the values in Table C of the diagnostic specifications. Replace any thermistor whose resistance falls outside the specified range. If both sensors test correctly, inspect the wiring harness and connectors for damage or corrosion, and consider the control board as a last resort if all other components check out.

The ice maker is not producing ice during a 4-blink fault because all loads are shut off by the control board, so there is no immediate safety hazard from the unit running. However, you should not attempt to bypass the fault or force the unit to operate without resolving the thermistor issue, as the sensors are critical for proper freeze and harvest cycle control.