LG · Oven Moderate

F1 — LG Range F1 — Upper Oven Thermistor Error

F1 means the upper oven temperature sensor (thermistor) is reading out of range.

Keep using it?
Yes, with caution
DIY difficulty
Moderate
Verified against
lg.com ↗

How to fix it

  1. Turn the range off at the breaker for 30 seconds to reset.
  2. If F1 returns, test the upper oven sensor for correct resistance and inspect its wiring.
  3. Replace the thermistor if out of spec.

Why it happens

Typical signs: Oven heats incorrectly or not at all · F1 on the display

  • Failed thermistor The upper oven temperature sensor has failed.
  • Sensor wiring/connector fault A damaged or loose sensor harness.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

  • LG Oven Temperature Sensor Common replacement
    Amazon →

Related repair guides

Oven Temperature Is Off — How to Calibrate It →

More LG oven codes

5b 5b — Sabbath Mode active (not a fault) CF1 CF1 — Left-front cooktop sensor open/short CF2 CF2 — Left-rear cooktop sensor open/short CF3 CF3 — Right-front cooktop sensor open/short CF4 CF4 — Rear Cooktop Sensor Error (Zone Varies by Model) F10 Range F10 — Door Locking System Failure

All LG codes → All oven codes →

Frequently asked questions

What does the F1 code mean on a LG oven?

F1 means the upper oven temperature sensor (thermistor) is reading out of range.

What causes the F1 code on a LG oven?

Failed thermistor: The upper oven temperature sensor has failed. Sensor wiring/connector fault: A damaged or loose sensor harness.

Is it safe to keep using a LG oven with a F1 error?

Yes, with caution. This is rated a moderate-severity fault.

How do I fix F1 on a LG oven?

Turn the range off at the breaker for 30 seconds to reset. If F1 returns, test the upper oven sensor for correct resistance and inspect its wiring. Replace the thermistor if out of spec.

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: lg.com.