mypros+
Error code reference

Frigidaire Ice Maker Error Code 4 blinks

Both bin and evaporator thermistors are out-of-range, all loads shut off and unit will not run.

Frigidaire codesFrigidaire ice maker codes

Both bin and evaporator thermistors are out-of-range, all loads shut off and unit will not run.

First step from the service manual

Test both thermistors' resistance and compare with Table C; replace any that are out of specification.

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

MyPros+ Max

Get the full diagnostic procedure for 4 blinks.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What 4 blinks means on a Frigidaire ice maker

The 4-blink error code on a Frigidaire ice maker indicates that both the bin thermistor and the evaporator thermistor have simultaneously reported resistance values outside of the acceptable range defined in Table C of the diagnostic specifications. Because both sensors are flagged at the same time, the control board treats the condition as a critical fault and shuts down all loads, meaning the compressor, fan motor, and water valve will all stop functioning. The unit will not attempt to run a harvest or freeze cycle until the fault is resolved.

Thermistors are negative temperature coefficient (NTC) sensors, meaning their resistance decreases as temperature rises. If a thermistor's resistance reading falls outside the expected range for the current ambient or refrigerant temperature, the control board flags it as out-of-range. When both sensors fail this check simultaneously, the most likely explanation is a shared wiring issue, a failed control board, or coincidental failure of both components. However, it is also possible that an extreme ambient temperature condition is causing both sensors to read outside their normal operating window.

The correct first diagnostic step is to test the resistance of each thermistor individually and compare those readings against Table C. A thermistor that reads open (infinite resistance) or short (near-zero resistance) is definitively failed and requires replacement. If both thermistors test within specification, the wiring harness and control board connections should be inspected for corrosion, pinched wires, or loose terminals before condemning the board itself.

Source: manufacturer service documentation.

Common causes of 4 blinks

  1. 01

    Wiring harness fault affecting both thermistors

    Wiring / connection

    A shared ground, corroded connector, or damaged wire in the harness that serves both thermistors can cause both sensors to report out-of-range values simultaneously. Inspect all connectors and wiring runs between the thermistors and the control board for visible damage or corrosion.

  2. 02

    Failed bin thermistor

    Part replacement

    The bin thermistor can fail open or short, producing a resistance value outside the range listed in Table C. Test resistance at the sensor leads and replace the thermistor if the reading does not match the specified range.

  3. 03

    Failed evaporator thermistor

    Part replacement

    The evaporator thermistor is exposed to repeated freeze and thaw cycles and can crack or degrade over time, causing an out-of-range resistance reading. Test resistance and compare to Table C, replacing the sensor if it is out of specification.

  4. 04

    Control board malfunction

    Part replacement

    If both thermistors test correctly and all wiring checks out, a faulty control board may be misreading the sensor inputs and falsely triggering the 4-blink fault. The board should be considered after sensors and wiring have been ruled out.

  5. 05

    Extreme ambient temperature

    Wiring / connection

    If the ice maker is installed in an environment with temperatures outside its rated operating range, both thermistors may produce readings that fall outside Table C values without the sensors themselves being defective. Verify the installation location meets the unit's ambient temperature requirements.

See the test procedure for each cause

Frequently asked questions about 4 blinks

What does 4 blinks mean on a Frigidaire ice_maker?
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.
How do I fix the 4-blink error on my Frigidaire ice maker?
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.
Will resetting the Frigidaire ice maker clear the 4-blink error?
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.
Is it safe to use my Frigidaire ice maker while it is showing a 4-blink error?
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.
How much does it cost to repair a Frigidaire ice maker with a 4-blink error?
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.

Related Frigidaire ice maker codes

All Frigidaire ice maker codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass