How do I fix LG Refrigerator Thermistor Replacement - Signs & How-To?

Follow the step-by-step diagnosis below. The most likely fix is identified by checking power, sensor resistance, and control-board signals in order — using a multimeter and the part numbers documented in the parts reference table.

Can I keep running the equipment with this fault active?

Generally no. Faults on Appliance units are emitted when a sensor, safety, or control circuit is outside its operating envelope. Running through an active fault risks compressor, heater, or control-board damage. Diagnose and clear the fault first.

What part is most commonly replaced for LG Refrigerator Thermistor Replacement - Signs & How-To?

The most frequently replaced parts for LG Refrigerator Thermistor Replacement - Signs & How-To are listed in the Parts Reference section of this guide with OEM part numbers and typical price ranges. Check the table for direct replacements.

Is LG Refrigerator Thermistor Replacement - Signs & How-To a DIY repair or do I need a technician?

Sensor swaps, fan motor replacements, and condenser cleaning are typical DIY-level repairs. Anything involving refrigerant, gas, or high-voltage (>240V) work requires a licensed technician for both safety and code-compliance reasons.

LG Refrigerator Thermistor Replacement - Signs & How-To

Q: What does LG Refrigerator Thermistor Replacement - Signs & How-To mean?

Warm freezer, error codes, or constant cooling? Bad thermistor. Replace it to restore accurate temperature control and normal cooling cycles.

LG Refrigerator Thermistor Replacement — What This Part Does

The thermistor is a temperature-dependent resistor that tells the control board how cold the refrigerator or freezer compartment is. LG refrigerators use multiple thermistors in different locations: fresh food compartment, freezer compartment, and evaporator/defrost circuit. When the board reads an open circuit, short, or out-of-range resistance from a thermistor, it cannot regulate cooling accurately and may display an error code or run continuously.

Thermistors fail when the resistor element drifts out of specification, opens, or shorts internally. Wiring problems at the connector or harness also cause invalid temperature signals. Ice buildup or physical damage to sensors mounted behind evaporator covers can interfere with readings. Because the thermistor is only one input to the control system, confirm the sensor itself is faulty before replacing it.

Jump to Replacement Steps

Signs It Needs Replacing

Freezer or fresh food compartment runs too warm The control board cannot see the real temperature and stops calling for cooling even though the compartment is above setpoint.
Compartment is too cold or freezes food A shorted thermistor reports a falsely high temperature, so the board runs the compressor continuously to compensate.
Temperature display shows error code or dashes LG refrigerators display fault codes when the board detects an open or shorted thermistor circuit.
Compressor runs non-stop without cycling off The board never sees the target temperature because the thermistor reading is stuck or invalid.
Inconsistent cooling or temperature swings An intermittent thermistor connection causes the board to cycle cooling erratically as the signal drops in and out.
Multimeter shows out-of-range resistance at the sensor Testing the thermistor terminals against a temperature-resistance chart reveals the sensor is open, shorted, or drifted far out of spec.

How to Replace It

Unplug the refrigerator from the wall outlet to disconnect all power before accessing any internal components or wiring.
Remove the freezer drawer, drawer rails, and any covers necessary to access the rear evaporator panel where the thermistor is mounted (location varies by model).
Remove the evaporator cover or panel by unscrewing or unclipping it to expose the thermistor assembly, typically clipped into the cover or secured with insulation.
Unplug the thermistor connector from the harness and inspect both the sensor leads and connector terminals for corrosion, ice damage, or broken wires.
Use a multimeter set to resistance (ohms) to measure across the two terminals on the thermistor and compare the reading to the temperature-resistance chart for your model.
If the reading is open, shorted, or far out of specification, remove the old thermistor from its mounting clip or cover and install the new thermistor in the exact same position.
Plug the new thermistor connector into the harness, ensuring it seats fully and locks in place.
Reinstall the evaporator cover, rails, and drawer in reverse order, making sure no wires are pinched and all clips and screws are secure.
Restore power, monitor the temperature display for normal readings, and verify the compartment cools to setpoint within a few hours without error codes.

The Part You Need

Part	Notes
LG refrigerator thermistor (temperature sensor)	Amazon \| Part number and location (freezer, fresh food, or evaporator) vary by model. Find your exact part number on the model and serial plate inside the refrigerator door or compartment, then cross-reference it with LG parts documentation or an authorized parts supplier.

If this part is failing you may also see one of these codes:

When to Call a Pro

If the new thermistor tests within specification but the temperature complaint or error code persists, the problem lies elsewhere in the cooling system: blocked airflow, failed evaporator fan, defrost system failure, or a faulty main control board. Diagnosing those requires checking defrost thermistors, thermal fuses, fan motors, and control board inputs. If you are not comfortable removing multiple panels, handling refrigerant-side components, or interpreting resistance charts, call a qualified appliance technician to complete the diagnosis and repair.