mypros+
Error code reference

LG Cooktop Error Code F6

Rear right top thermistor fault.

LG codesLG cooktop codes

Rear right top thermistor fault.

First step from the service manual

Check CN 03 (Right Module); thermistor should read 500~550 K ohms at room temperature.

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 F6.

  • 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 F6 means on a LG cooktop

The F6 error code on an LG cooktop indicates a fault in the rear right top thermistor circuit. The thermistor is a temperature-sensing resistor embedded in or near the rear right heating zone. It continuously reports temperature data to the control module, allowing the unit to regulate heat output and prevent overheating. When the control board detects a reading outside the expected range from this sensor, it triggers the F6 code and typically disables the affected burner or zone as a safety precaution.

Diagnosis begins at connector CN 03, which is the Right Module connection point. At room temperature, a properly functioning thermistor should read between 500 and 550 K ohms. A reading significantly above or below this range points to a faulty thermistor. An open circuit (infinite resistance) usually indicates a broken or disconnected thermistor, while a very low resistance reading suggests an internal short. Wiring issues between the thermistor and the control board, such as damaged insulation, corroded terminals, or a loose connector at CN 03, can also produce out-of-range readings and trigger the fault.

In some cases, the fault originates at the control board itself rather than the thermistor. If the thermistor resistance checks out correctly and the wiring harness shows no damage or corrosion, the Right Module or main control board may be misreading the sensor signal. Thermal stress from repeated high-heat cycles can degrade both the thermistor element and the connector contacts over time, making intermittent faults more likely on older units.

Source: manufacturer service documentation.

Common causes of F6

  1. 01

    Faulty rear right thermistor

    Part replacement

    The thermistor itself has failed and is producing a resistance value outside the 500 to 550 K ohm range at room temperature. This is the most common cause and is confirmed by measuring resistance directly at the sensor leads.

  2. 02

    Loose or corroded connector at CN 03

    Wiring / connection

    The Right Module connector CN 03 may be partially seated, corroded, or damaged, causing an intermittent or open circuit. Inspect the connector for discoloration, bent pins, or carbon tracking and reseat or replace as needed.

  3. 03

    Damaged wiring harness

    Part replacement

    The wiring between the thermistor and CN 03 may have cracked insulation, a broken conductor, or heat damage from proximity to the burner. Visually trace the harness and use a continuity tester to find any break.

  4. 04

    Faulty Right Module or control board

    Part replacement

    If the thermistor reads correctly and the wiring is intact, the Right Module connected at CN 03 may be misinterpreting the sensor signal due to internal board damage. This is typically diagnosed after ruling out the thermistor and wiring.

See the test procedure for each cause

Frequently asked questions about F6

What does F6 mean on a LG cooktop?
F6 on an LG cooktop indicates a rear right top thermistor fault. The cooktop has detected that the temperature sensor for the rear right burner zone is reading outside its expected resistance range. The affected zone is typically disabled until the fault is resolved. Diagnosis starts with checking connector CN 03 on the Right Module and measuring the thermistor resistance, which should be 500 to 550 K ohms at room temperature.
Can I fix the F6 error on my LG cooktop myself?
A knowledgeable DIYer comfortable working with appliance electronics can perform the basic diagnostic steps, including checking the CN 03 connector and testing thermistor resistance with a multimeter. If the thermistor or wiring is the issue, replacing those components is manageable with the right parts. However, if the Right Module or control board is at fault, professional repair is recommended due to the complexity and cost of those components.
Is it safe to keep using my LG cooktop when the F6 code is showing?
The F6 code typically disables the rear right burner zone, so that specific area should not be used while the fault is active. Other zones on the cooktop may continue to function normally. It is not advisable to attempt to override or ignore the fault, as the thermistor plays a key role in preventing overheating in that zone.
How much does it cost to repair an F6 error on an LG cooktop?
Repair costs vary depending on the root cause. A replacement thermistor is generally an inexpensive part, typically in the range of $15 to $50 for the component. If the Right Module or control board needs replacement, parts alone can range from $80 to $250 or more. Adding professional labor, total repair costs can fall anywhere from $100 to $400 depending on the diagnosis.
Will resetting my LG cooktop clear the F6 error code?
Resetting the cooktop by powering it off at the breaker for a few minutes may temporarily clear the F6 code, but the fault will return if the underlying problem is not fixed. The thermistor or its circuit has a measurable fault that the control board will detect again on the next cycle. A reset is useful for confirming whether the fault is intermittent, but it is not a substitute for proper diagnosis and repair.

Related LG cooktop codes

All LG cooktop codes
View all 16 LG cooktop codes

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

Get Started

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