What F4 Means
F4 on Frigidaire sensor-cook microwaves means the humidity sensor read open for more than 60 seconds during cooking.
Common Causes of F4
- Disconnected sensor
- Failed humidity sensor
- Wiring or board fault
🔧 One Safe Check You Can Try
Unplug the microwave for a minute and restore power. Use timed cooking in the meantime. If F4 returns on sensor programs, book service.
⚠ Why You Shouldn't Go Further Than That
- Accessing the sensor requires opening the cabinet near the high-voltage capacitor and magnetron circuit.
- Damage caused during a repair attempt may not be covered by your warranty — check your warranty terms first.
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.