Samsung Microwave F2 Error — Temperature Sensor Fault

What Does This Error Mean?

F2 on a Samsung microwave is a temperature sensor (thermistor) fault — the small probe that monitors cavity or magnetron temperature is reading out of range.
Power-cycle and try again.
If F2 persists, the sensor or its wiring needs replacement — a service-tech repair (100–200 USD).
The microwave will refuse to cook until the sensor is fixed because temperature monitoring is part of the safety system.

Affected Models

Samsung over-the-range microwave
Samsung countertop microwave
Samsung built-in microwave
Samsung MS series

Common Causes

Thermistor failed (open or shorted)
Sensor wire disconnected from the control board
Sensor wire damaged by years of vibration or heat
Connector loose at the controller
Control board sensor input damaged

How to Fix It

Unplug for 10 minutes.

Pull the plug.
Wait 10 minutes for capacitors to discharge.
Plug back in.
Some F2 events are transient and clear after a power cycle.
Try cooking briefly to confirm.
Don't disassemble the microwave.

The thermistor lives inside the microwave near the magnetron, surrounded by high-voltage components.
Microwave capacitors hold lethal voltage for days after unplugging.
This is genuinely service-tech-only territory — don't open the unit.
Check the install age.

Thermistors are typically reliable — failure within 2 years is rare.
If your microwave is 10+ years old, sensor failure is normal end-of-life maintenance.
For built-ins worth more than the repair, fix it; for over-the-range or countertop units that are aged, replace the whole microwave.
Schedule service for repair.

Provide model and serial numbers.
Samsung-authorized centers can typically replace the thermistor in one visit.
Job is 1–2 hours.
Out of warranty, expect 100–200 USD all-in.
Free under warranty.
Or replace the microwave.

If the unit is over 7 years old and out of warranty, a new microwave is often more economical than repair.
Compare the repair quote to the price of a comparable new unit before deciding.
Built-ins are the exception — those are worth repairing because replacement involves cabinetry work.

Frequently Asked Questions

Will the microwave still operate with F2?

Most Samsung microwaves block all cooking when F2 is active.
The thermistor is part of the magnetron protection chain, and without it the safety circuit can't run.
You'll get F2 every time you try to start a cook.
The microwave essentially won't function until repaired.

Is replacing the microwave wasteful?

Depends on the unit's age.
Repairing a 3-year-old built-in is cost-effective and reduces waste.
Repairing a 12-year-old countertop unit isn't — newer microwaves are more efficient and usually have better safety features.
Recycle the old unit through e-waste programs rather than throwing it out.