Maytag · Microwave Moderate

F4E1 — Cavity Temperature Thermistor Fault

F4E1 indicates a fault in the cavity temperature thermistor or its wiring — the sensor is reading open, shorted, or out of range. It is the temperature thermistor specifically, not a humidity sensor.

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

How to fix it

  1. Unplug the microwave for 5 minutes.
  2. Access the sensor location and inspect wiring for pinches or burns.
  3. Disconnect the sensor and measure resistance — a near-zero reading confirms a short.
  4. Replace the sensor if shorted.
  5. If sensor reads normally when disconnected, inspect the harness for damage.
  6. Replace the harness or main control board as needed.

Why it happens

Typical signs: F4E1 at startup · Sensor cycles unavailable · Display flashes the error

  • Shorted thermistor Sensor element internally shorted.
  • Pinched/chafed sensor wire Wire insulation rubbed through to chassis.
  • Moisture in connector Water or grease in connector creating short.
  • Failed control board Sensor input circuit shorted on the ACU.

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.

  • Maytag microwave sensor Common replacement
    Amazon →

More Maytag microwave codes

door 'door' — Door Not Closed / Open Reminder F1E1 F1E1 — Main Control Board Failure F1E2 F1E2 — Control / User-Interface Fault F2E1 F2E1 — Stuck Key on Keypad F2E2 F2E2 — User Interface Mismatch F3E1 F3E1 — Humidity Sensor Failure

All Maytag codes → All microwave codes →

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: producthelp.maytag.com.