What F1 Means
F1 on Whirlpool-platform Kenmore microwaves means the temperature thermistor is reading as an open circuit, with no heat detected — the microwave stops rather than run without reliable temperature feedback.
Common Causes of F1
- Failed temperature thermistor
- Damaged or disconnected thermistor wiring
- Control board misreading the sensor signal
🔧 One Safe Check You Can Try
Power-cycle by unplugging the microwave for a few minutes; if F1 returns on the next use, that confirms a genuine thermistor-circuit fault rather than a one-time glitch.
⚠ Why You Shouldn't Go Further Than That
- Microwaves store a lethal electrical charge in their high-voltage capacitor even after being unplugged — the housing should never be opened except by someone trained in high-voltage safety.
- The thermistor sits inside the cabinet near other high-voltage components, making a DIY check genuinely dangerous, not just inconvenient.
- A part swapped without confirming the fault first, on a component this expensive and risky to access, is a costly mistake to get wrong.
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.