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Error code reference

Liebherr Refrigerator Error Code F1

Refrigerator compartment air sensor defective; appliance enters emergency mode with compressor 20 minutes ON…

Liebherr codesLiebherr refrigerator codes

Refrigerator compartment air sensor defective; appliance enters emergency mode with compressor 20 minutes ON and 40 minutes OFF.

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What F1 means on a Liebherr refrigerator

The F1 error code on a Liebherr refrigerator indicates that the refrigerator compartment air temperature sensor has been detected as defective. This sensor, also called a NTC (negative temperature coefficient) thermistor, is responsible for continuously monitoring the air temperature inside the fresh food compartment and reporting that data to the control board. When the control board receives a signal that falls outside the expected resistance range for the sensor, or detects an open or short circuit in the sensor circuit, it registers the F1 fault and can no longer rely on that temperature input for normal regulation.

Because the refrigerator compartment temperature can no longer be accurately monitored, the appliance enters a predefined emergency operating mode. In this mode, the compressor runs on a fixed cycle of 20 minutes ON followed by 40 minutes OFF, regardless of actual internal temperatures. This keeps the unit running and provides some degree of cooling, but it is not an optimized cycle and cannot respond to actual load conditions or ambient temperature changes. Food safety may be compromised over time if the fault is not addressed promptly.

The most common root causes of F1 include a failed thermistor, damaged wiring or connectors between the sensor and the control board, or moisture intrusion that has corroded the sensor or its connector terminals. In some cases, the control board itself may be misreading a signal from an otherwise functional sensor, though this is less common. Proper diagnosis requires checking sensor continuity, resistance values at known temperatures, and inspecting wiring harness integrity before replacing components.

Source: manufacturer service documentation.

Common causes of F1

  1. 01

    Failed NTC temperature sensor

    Part replacement

    The thermistor in the refrigerator compartment can fail due to age, moisture exposure, or physical damage, causing it to read outside the acceptable resistance range or produce no signal at all. Testing the sensor with a multimeter for continuity and resistance at a known temperature will confirm whether it has failed.

  2. 02

    Damaged or disconnected wiring harness

    Wiring / connection

    The wiring between the compartment sensor and the main control board can develop breaks, kinks, or loose connector pins, particularly in areas subject to vibration or repeated door movement. Visually inspecting the harness and checking for continuity at the connector terminals can identify this issue.

  3. 03

    Corroded or oxidized connector terminals

    Wiring / connection

    Moisture inside the refrigerator compartment can reach the sensor connector and cause corrosion on the terminals, increasing resistance in the circuit to a point where the control board reads the sensor as faulty. Cleaning or replacing the connector may restore proper communication.

  4. 04

    Sensor mounting or contact issue

    Wiring / connection

    If the sensor has shifted out of its correct mounting position, it may not be reading compartment air temperature accurately, leading to out-of-range readings that trigger the fault. Repositioning and securing the sensor in its proper bracket can resolve this without parts replacement.

  5. 05

    Defective main control board

    Part replacement

    In less common cases, the control board itself may be failing to correctly interpret a signal from an otherwise functional sensor, registering a fault that does not reflect actual sensor failure. This is typically diagnosed only after the sensor and wiring have been confirmed good.

See the test procedure for each cause

Frequently asked questions about F1

What does F1 mean on a Liebherr refrigerator?
F1 indicates that the refrigerator compartment air temperature sensor has been detected as defective by the control board. Because accurate temperature monitoring is no longer possible, the unit enters an emergency mode where the compressor cycles on a fixed schedule of 20 minutes ON and 40 minutes OFF. This keeps the unit running but does not replace proper temperature-controlled operation. The sensor or its associated wiring should be inspected and repaired as soon as possible.
Can I fix the F1 error on my Liebherr refrigerator myself?
A knowledgeable DIYer can inspect the sensor wiring, check connector terminals for corrosion, and test the sensor with a multimeter to determine whether the component itself has failed. If the sensor requires replacement, it is a relatively accessible repair involving disconnecting the old sensor and installing a compatible replacement. However, if the wiring harness or control board is involved, professional repair is recommended to avoid further damage.
Is it safe to keep using my Liebherr refrigerator while the F1 code is active?
The appliance will continue to run in emergency mode with the compressor cycling on a fixed 20-minutes-ON and 40-minutes-OFF schedule. This provides some cooling but may not maintain safe temperatures consistently, especially during warm ambient conditions or with a full load of food. It is advisable to check internal temperatures with a thermometer and minimize the time food is stored in the unit until the fault is resolved.
Will resetting my Liebherr refrigerator clear the F1 error code?
A power reset may temporarily clear the displayed error code, but if the underlying sensor or wiring fault is still present, the F1 code will return once the control board performs its self-diagnostic checks. Resetting the unit does not repair the defective sensor or correct any wiring issues. Permanent resolution requires addressing the actual hardware fault.
How much does it cost to repair a Liebherr F1 error code?
Repair costs depend on whether the fault is in the sensor itself, the wiring, or the control board. A replacement NTC temperature sensor typically costs in the range of $20 to $80 for the part alone. If a technician is needed for diagnosis and installation, total repair costs including labor can range from $100 to $300 or more, with control board replacement representing the higher end of that range.

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