What F9 (Upper Oven Not Heating Properly) Means
F9 indicates the upper oven is not heating properly, per LG's range Help Library article - broader than F6's specific heating-element fault, covering a general failure of the oven to reach or maintain its set temperature.
Common Causes of F9 (Upper Oven Not Heating Properly)
- Heating element fault
- Thermistor fault preventing accurate temperature control
- Control board fault
🔧 One Safe Check You Can Try
Press the CLEAR/OFF key and try the original function again; if it reappears, cycle the circuit breaker for 30 seconds before trying once more.
⚠ Why You Shouldn't Go Further Than That
- If F9 returns after a breaker cycle, don't rely on the upper oven for cooking that requires reaching a specific safe internal food temperature until a technician has diagnosed the fault - undercooked food from an oven that isn't truly reaching its set temperature is a genuine food-safety risk, not just an inconvenience.
- Because F9 can stem from several different underlying faults (element, sensor, or board), a technician's diagnostic approach is needed to identify the actual cause rather than guessing at a part to replace.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.