What does LG Range F5 Error Code - Causes & Fix mean?

F5 on an LG range means a lower oven thermistor error. Most often a bad thermistor or loose connection. Reset power, then replace the sensor.

How do I fix LG Range F5 Error Code - Causes & Fix?

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 F5 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 Range F5 Error Code - Causes & Fix?

The most frequently replaced parts for LG Range F5 Error Code - Causes & Fix 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 Range F5 Error Code - Causes & Fix 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 Range F5 Error Code - Causes & Fix

LG Range F5 Error Code — What It Means

The F5 error code on an LG range signals a lower oven thermistor error. The thermistor is a temperature sensor that monitors the lower oven cavity. When the control board detects an open circuit, short circuit, or out-of-range reading from this sensor, it triggers F5 and stops heating to protect the appliance. This code is specific to LG ranges and ovens. Other LG appliances may use F5 for different faults, so confirming you have a range matters.

Jump to Fix

Common Causes

Failed lower oven thermistor The thermistor itself has drifted out of spec or failed internally, sending incorrect resistance readings to the control board.
Loose or corroded connector The plug between the thermistor wire and the main harness has pulled apart, corroded, or developed a poor contact.
Broken or shorted thermistor wiring The wire harness running from the lower oven sensor to the control has been pinched, melted, or cut, creating an open or short circuit.
Control board misreading the sensor circuit The main control or oven control board has a faulty input circuit that cannot correctly read a good thermistor.

Step-by-Step Fix

Turn off the range at the circuit breaker and wait at least 30 seconds to clear the control’s memory, then restore power as LG’s reset procedure.
Press CLEAR/OFF or Power ON/OFF on the control panel to dismiss the code and see if normal operation resumes.
Run a test cycle on the lower oven and watch for the F5 code to return, confirming whether the fault is persistent or intermittent.
Disconnect power again and remove the lower oven’s rear or side access panel to locate the thermistor probe mounted inside the oven cavity.
Inspect the thermistor connector and harness for burn marks, loose pins, corrosion, or broken wires, and reseat or repair any visible damage.
Test the thermistor resistance with a multimeter (consult your model’s service manual for the correct value at room temperature) and replace the sensor if it reads open, shorted, or out of range.
Replace the main control board only if the thermistor and wiring test good but the F5 code persists, indicating a board-side circuit fault.

Parts Often Needed

Part	Notes
LG lower oven thermistor	Amazon \| Order by your range’s full model number to make sure the correct probe length and connector type.
LG range main control board (oven control)	Amazon \| Replace only after confirming the thermistor circuit is intact and the sensor itself tests within specification.

When to Call a Pro

Call a qualified appliance technician if you are not comfortable working around 240-volt circuits or removing oven panels. A pro can quickly test the thermistor circuit with the correct resistance table for your model, identify whether the fault is in the sensor or the board, and install the right part without risking further damage. If the code reappears immediately after a thermistor replacement, the control board likely needs professional-level diagnostics and replacement.