Open thermal sensor; excessive heat condition in cavity.
Model compatibility: GE reuses codes across series and model years, so F1 may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.
Plain language
What this code means
Open thermal sensor; excessive heat condition in cavity.
Signs
Symptoms you may notice
The code may appear after the cavity becomes unusually hot.
Other components may be disabled because the control cannot trust the sensor input.
Operation may stop when the control sees an implausible reading.
The fault may return shortly after restart if the sensor circuit remains open or shorted.
Why it happens
Possible causes
An internal high-voltage/heating-system problem that requires qualified microwave service.
An open/shorted thermal sensor or related wiring.
Moisture/temperature conditions affecting the sensor circuit.
An actual overheating condition caused by abnormal airflow or operation.
A sensor or thermistor that has drifted outside its expected range.
Before you call
Safe checks you can make
These are simple, non-hazardous checks only. If anything is unclear, stop and contact a technician.
Check that exterior intake/exhaust openings are not blocked.
Do not disconnect internal sensors just to “test” whether the code clears; that can create additional faults.
Note whether the code appears immediately or only after heating/cooling begins; that timing is useful for diagnosis.
Do not remove the microwave cover or attempt internal sensor/high-voltage testing.
Important safety warning. Do not attempt repairs involving electrical components, gas, water lines, refrigerant or sealed systems. Unplug the appliance if it is safe to reach the outlet, and leave internal diagnostics to a qualified technician.
Seeing this code on your GE appliance?
Book a specialist visit for a clear estimate and approval before any repair.
You submit a request with your appliance model and symptom, we confirm an appointment window, and a technician performs an on-site diagnosis. You then receive a clear estimate and decide whether to proceed before any repair begins.
Yes. We provide an upfront estimate after diagnosis. No parts are ordered or installed until you approve the work, so there are no surprise charges.
Replacement parts are selected for the exact model and confirmed with you before ordering or installation.
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