Maytag Microwave Error Code F1 — Open Thermistor Sensor
What this means
The F1 error code on Maytag microwaves indicates the oven cavity thermistor (temperature sensor) has an open circuit. The thermistor monitors internal temperature to prevent overheating and to support sensor cooking programs. An open thermistor means the circuit is broken, and the microwave cannot determine the internal temperature. The microwave will not operate until the sensor is replaced.
Step-by-step fix
3 stepsReset the microwave
Unplug the microwave for 5 minutes and plug it back in. A temporary sensor glitch may clear with a full power reset.
If the error appeared after a long cooking session, let the microwave cool for 30 minutes before resetting.
Locate and test the thermistor
Unplug the microwave. Remove the outer cabinet cover. SAFETY: Do not touch the high-voltage capacitor. Locate the thermistor — usually a small bead or capsule on the oven cavity wall. Disconnect its wires and test resistance with a multimeter. At room temperature, it should read approximately 50,000–60,000 ohms. An infinite (open) reading confirms failure.
Set your multimeter to the 200kΩ range to get an accurate reading on the high-resistance thermistor.
Replace the thermistor
Remove the mounting clip or screw holding the thermistor. Install the new one in the same position. Reconnect the wires (no polarity) and reassemble the cabinet.
Maytag microwaves are often manufactured by Whirlpool — Whirlpool parts frequently cross-reference for Maytag models.
When to call a professional
Microwave repair involves exposure to a high-voltage capacitor that can hold a lethal charge. Professional repair is recommended unless you have specific microwave repair experience.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
Learn more about our sourcesParts you may need
Oven Cavity Thermistor
Part #W10250879 · $15–$30
Required if thermistor reads open (infinite)
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