LG Cooktop Error Code F3

F3 on an LG cooktop means the control system is getting no feedback signal from the front left cooking zone. The cooktop monitors each induction zone through its own module, and when that communication is lost, F3 is displayed to alert you that the front left zone cannot operate safely. The cooktop will disable that zone until the fault is corrected.

The front left cooking zone will be disabled while the F3 error is active, so you cannot use that specific burner. The remaining cooking zones may continue to function, but you should address the fault promptly to avoid any secondary damage to the control board or wiring from an unresolved module fault. Do not attempt to bypass the error code to force the front left zone to operate.

Repair costs vary depending on the root cause. If the fix is simply reseating the CN01 connector, you may only pay for a service call, typically in the range of $75 to $150. Replacing a front IH module or wiring harness generally adds $100 to $300 or more in parts, while a main control board replacement can bring the total repair cost to $200 to $500 or higher depending on your region and the technician's labor rate.

If you are comfortable working with appliance electronics, you can begin by checking the CN01 connector on the front IH module for a loose or unseated connection, which sometimes resolves the issue without any parts. Beyond that initial check, diagnosing a failed wiring harness or replacing an IH module or control board requires disassembly and basic electrical knowledge. If you are not confident working inside the cooktop, a qualified technician is the safer choice.

Powering the cooktop off at the circuit breaker for a few minutes and then restoring power will clear the displayed error temporarily, but if the underlying connection or component fault is still present, F3 will return as soon as the control system checks the front left zone again. A reset is useful for confirming whether the fault is intermittent, but it is not a repair.