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Error code reference

LG Refrigerator Error Code F1+F2

Failure of ambient temperature sensor

LG codesLG refrigerator codes

Failure of ambient temperature sensor - sensor is disconnected or shorted.

First step from the service manual

Press both FOOD and TEMP buttons simultaneously for 1 second to verify; if all LEDs except failure LEDs turn on, ambient sensor is confirmed faulty.

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

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What F1+F2 means on a LG refrigerator

The F1+F2 error code on an LG refrigerator indicates a failure of the ambient temperature sensor, also called the room temperature sensor. This sensor monitors the surrounding environmental temperature and feeds that data to the control board, which uses it to adjust compressor cycles and cooling performance. When the control board detects that the sensor circuit is either open (disconnected) or shorted, it triggers this combined error code to alert the user and technician that the ambient sensing input is compromised.

The two conditions that trigger F1+F2 are a disconnected sensor and a shorted sensor. A disconnected sensor typically means the wiring harness connector has come loose from the sensor or the sensor lead has broken. A shorted sensor means the internal resistance of the sensor has collapsed, causing the signal wire to read a near-zero resistance that falls outside the normal operating range. Both conditions produce an invalid temperature reading, preventing the control board from accurately managing cooling output.

To confirm the fault, press both the FOOD and TEMP buttons simultaneously and hold for 1 second. If all LEDs on the display illuminate except the failure indicator LEDs, this confirms the ambient temperature sensor is the source of the fault. This diagnostic mode isolates the sensor fault from other potential display or board issues, giving a clear confirmation before any parts are ordered or replaced.

Source: manufacturer service documentation.

Common causes of F1+F2

  1. 01

    Loose or disconnected wiring harness

    Wiring / connection

    The connector between the ambient temperature sensor and the wiring harness may have come loose over time due to vibration or movement of the unit. Inspect the sensor connector for a secure fit and check for any pulled or broken wires at the connector terminals.

  2. 02

    Failed ambient temperature sensor

    Part replacement

    The sensor itself may have failed internally, resulting in a shorted or open circuit. This is confirmed when the wiring harness is intact and connected but the resistance reading from the sensor falls outside the expected range for the current room temperature.

  3. 03

    Damaged sensor wiring

    Part replacement

    The wire running from the ambient sensor to the control board may be pinched, chafed, or broken at a stress point, causing either an open or short circuit condition. Trace the full length of the sensor wiring for visible damage.

  4. 04

    Corroded or dirty connector terminals

    Wiring / connection

    Moisture or dust accumulation at the sensor connector can increase resistance in the circuit or cause intermittent contact, which the control board reads as a sensor fault. Inspect the terminals for oxidation or debris and clean carefully.

  5. 05

    Faulty main control board

    Part replacement

    If the sensor and all wiring test correctly but the error persists, the control board input circuit for the ambient sensor may have failed. This is the least common cause and should only be considered after the sensor and wiring are ruled out.

See the test procedure for each cause

Frequently asked questions about F1+F2

What does F1+F2 mean on a LG refrigerator?
F1+F2 on an LG refrigerator indicates a failure of the ambient temperature sensor. The sensor is either disconnected from the wiring harness or has developed an internal short. You can confirm this fault by pressing the FOOD and TEMP buttons simultaneously for 1 second: if all LEDs except the failure LEDs illuminate, the ambient sensor is confirmed as the problem.
Can I fix F1+F2 on my LG refrigerator myself?
If the cause is simply a loose connector at the ambient temperature sensor, you may be able to reconnect it yourself after locating the sensor and its harness. If the sensor itself has failed or the wiring is damaged, replacing those components requires basic electrical knowledge and comfort working with appliance wiring. A control board replacement, if needed, is more complex and typically benefits from professional service.
Is it safe to keep using my LG refrigerator with the F1+F2 error?
The refrigerator may continue to cool in some capacity, but without accurate ambient temperature data the control board cannot optimize its performance, which could lead to inconsistent temperatures. Food safety could be at risk if cooling becomes unreliable. It is best to address the fault promptly rather than continuing to rely on the appliance while the sensor is faulty.
How much does it cost to repair the F1+F2 error on an LG refrigerator?
If only the ambient temperature sensor needs replacement, parts typically cost in the range of $15 to $50 depending on the model, with labor adding $75 to $150 if a technician is involved. If the wiring harness or control board is at fault, repair costs can range from $150 to $400 or more. Getting a diagnosis first will help avoid paying for unnecessary parts.
Will resetting my LG refrigerator clear the F1+F2 error code?
A reset may temporarily clear the displayed error code, but the fault will return if the underlying problem with the ambient temperature sensor or its wiring has not been fixed. Resetting without repairing is not a solution. Use the diagnostic button test (FOOD and TEMP held for 1 second) to confirm whether the sensor fault is still active after any reset.

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