What F3T3 Means
F3T3 names the hood temperature thermistor or its wiring. The hood thermistor monitors the temperature under the microwave, above the cooktop, and on many models it is what makes the vent fan speed up automatically when the cooktop below gets hot.
Common Causes of F3T3
- Grease filters blocked, trapping heat under the unit
- Vent path restricted
- Thermistor connector loose
- Hood thermistor failed
- Genuine high temperature from the cooktop below
🔧 One Safe Check You Can Try
Check the vent and the grease filters underneath the microwave first, since a blocked filter traps heat right where this sensor sits. Wash the metal grease filters in hot detergent solution or the dishwasher and dry them before refitting. Switch the microwave off at its circuit breaker for one minute, restore power, then run a short heating test with a cup of water to verify operation, which is the check Maytag asks for. If the code returns with clean filters and a clear vent, the thermistor needs replacing.
⚠ Why You Shouldn't Go Further Than That
- A microwave oven holds a high voltage capacitor that can retain a dangerous charge long after the appliance is unplugged, so the cabinet is never opened at home under any circumstances.
- An over-the-range unit is mounted above a cooking surface at head height and is heavy enough to need two people and a support to remove safely.
- Let the cooktop and the underside of the microwave cool before removing filters.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.