F21Serious
Maytag Refrigerator F21 Error Code
The freezer temperature sensor is reading out of range or failed.
Common causes
- Faulty freezer thermistor
- Wiring issue
- Control board failure
How to fix it
- Unplug refrigerator and let it sit for 5 minutes.
- Check the freezer thermistor connector at the control board.
- Measure resistance of thermistor; should be around 10k ohms at 77°F.
- Replace thermistor if out of spec.
⚠ When to call a pro: If wiring or control board appears damaged, or code returns after replacing thermistor.
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Always unplug the appliance (and turn off the water for washers/dishwashers) before inspecting. These guides are for information only and are not a substitute for a professional repair.