What F3T3 Means
JennAir's F3T3 page names the hood temperature thermistor or the associated wiring. That sensor watches the temperature under the microwave, where the hood sits over the cooking surface, and it is what triggers the automatic fan on many models.
Common Causes of F3T3
- A hood temperature thermistor that has failed
- Heavy grease loading on the filters altering the airflow under the unit
- A wiring problem in the hood sensor circuit
🔧 One Safe Check You Can Try
Let everything cool, clean the grease filters underneath, and reset at the breaker for a minute - a filter clogged solid changes the temperature the hood sensor sees and is worth eliminating first.
⚠ Why You Shouldn't Go Further Than That
- This sensor sits directly above a cooking surface, so any work in that area follows the range being properly off and cool, and on a gas range the gas supply shut off first.
- A hood sensor that misreads can leave the automatic fan failing to start over a hot cooktop, which is a fire-safety consideration rather than a convenience one.
- Reaching the sensor means lowering the microwave from its wall plate and cabinet bolts, and taking that weight single-handed is how those bolts get bent.
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.
Technical Reference
- Code
- F3T3
- Appliance
- JennAir microwave
- Maker documentation
- JennAir owner manuals and use & care guides
- Checked
- September 2026
Code meanings can change between control generations. Before acting on a code, match the full model number on your appliance's rating label against the manual for that model. We are an independent repair service, not affiliated with Whirlpool Corporation.