GE · Microwave Serious

F1 — Open Thermal Sensor (Overheating)

F1 means the thermal sensor read open due to excessive heat in the cavity — an overheat protection fault.

Keep using it?
Limited use only
DIY difficulty
Moderate
Verified against
products.geappliances.com ↗

How to fix it

  1. Unplug the microwave for a minute to reset and let it cool.
  2. Make sure the top/rear vents are not blocked (OTR units).
  3. If F1 returns, test/replace the thermal sensor.

Why it happens

Typical signs: Microwave stops/beeps · F1 on the display · Unit ran hot

  • Blocked vents / overheating Restricted airflow (especially on over-the-range units) traps heat.
  • Failed (open) thermal sensor The cavity thermal sensor has failed open.
  • Sensor wiring fault A broken connector or wire to the sensor.

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.

  • GE Microwave Thermal Sensor Common replacement
    Amazon →

More GE microwave codes

DOOR DOOR — Door not fully closed / open too long F10 F10 — Shorted Touch Screen F11 F11 — Shorted Touchpad / Keypad F2 F2 — Shorted Thermal Sensor F3 -E0 F3 — Shorted Touch Panel F3 F3 — Shorted Touch Pad

All GE codes → All microwave codes →

Frequently asked questions

What does the F1 code mean on a GE microwave?

F1 means the thermal sensor read open due to excessive heat in the cavity — an overheat protection fault.

What causes the F1 code on a GE microwave?

Blocked vents / overheating: Restricted airflow (especially on over-the-range units) traps heat. Failed (open) thermal sensor: The cavity thermal sensor has failed open. Sensor wiring fault: A broken connector or wire to the sensor.

Is it safe to keep using a GE microwave with a F1 error?

Limited use only. This is rated a serious-severity fault.

How do I fix F1 on a GE microwave?

Unplug the microwave for a minute to reset and let it cool. Make sure the top/rear vents are not blocked (OTR units). If F1 returns, test/replace the thermal sensor.

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: products.geappliances.com.