On LG ranges and wall ovens, F1, F2 and F4 are temperature sensor (thermistor) errors, F3 is a touch pad key error, F6, F9 and F19 are heating faults, F7 and F17 are convection fan errors, and F10 and F20 are door-lock faults. LG’s standard first step is to press CLEAR/OFF and retry; if the code returns, turn off the circuit breaker for 30 seconds. H5, PF and 5b are messages, not faults.
LG’s standard first step
- Press CLEAR/OFF and try again
For most F codes LG’s first instruction is to press the CLEAR/OFF key and repeat the function you were using.
- If the code returns, reset at the breaker
Switch the circuit breaker for the range off, wait 30 seconds and switch it back on. For F3 and several cooktop codes, LG goes straight to the breaker reset.
- If it still returns, book service
A code that survives a breaker reset is a real fault and needs a technician.
The full code list
| Code | What LG says it means |
|---|---|
| F1, F2 | Upper oven thermistor error |
| F3 | Touch pad sensor key error |
| F4 | Lower oven thermistor error |
| F6 | Upper oven heating error |
| F7 | Upper convection fan error |
| F8, F18 | Oven meat probe error |
| F9 | Upper oven not heating properly |
| F10 | Door locking system failure (upper oven) |
| F11 | Communication error |
| F16 | Oven sensor issue |
| F17 | Convection fan error |
| F19 | Oven heating error |
| F20 | Door locking system failure (lower oven) |
| F21, F22, F24, F25 | Steam sensor failure |
| F27 | Cooling fan stalled or locked during self-clean |
| F33, F34 | Front induction burner temperature sensor error |
| F36 | Transistor error |
| F38 | Communication error between main board and inverter |
| F42 | Voltage error |
| F45, F46 | Fan error |
| F51, F52, F56, F59 | Griddle sensor, short, heating and not-heating errors |
| F62, F69 | Sous vide sensor and not-heating errors |
| H5 | Cooktop is still hot (above about 150°F) — an indicator, not an error |
| PF | Power was interrupted to the appliance |
| 5b | Sabbath mode is on — not an error |
Only some of these appear on any one model; a basic electric range will never show the induction, steam, griddle or sous vide codes.
H5, PF and 5b: Not faults
H5 simply means the cooktop surface is still hot; if it never goes out after the cooktop has cooled, reset the breaker for 30 seconds. PF means power was interrupted — press CLEAR/OFF and restart. 5b is Sabbath mode: LG’s steps are to press Bake, set a temperature with the +/- keys, press Start, then hold the Clock key for 3 seconds to turn it off.
Thermistor and heating codes
F1, F2 and F4 mean the oven’s temperature probe is reading outside its expected range. F6, F9 and F19 mean the oven is not heating as it should. A sensor that has drifted can leave the oven heating poorly or not at all — see oven not heating, element problems and oven takes too long to preheat. F7 and F17 are fan faults; our convection fan guide covers the checks.
Door lock codes
F10 (upper oven) and F20 (lower oven) are door-lock failures, often seen after a self-clean cycle. Do not force the door. See self-clean cycle won’t start or won’t unlock, and oven door won’t close if the door itself is misaligned.
Cooktop, steam and other codes
Induction, steam, griddle and sous vide codes (F21 to F69) are specific to higher-end models, and LG’s instruction for nearly all of them is to reset the breaker for 30 seconds. F11 and F38 are board-to-board communication faults; F42 is a voltage error and can point to a supply problem at the house panel.
When to call for service
Thermistor, lock, fan, voltage and communication codes that return after a breaker reset need a technician. See our oven repair cost guide to weigh repair against replacement.
