F9

Kenmore Microwave Error Code F9 — Inverter Failure

Professional 45–60 minutes No tools needed

What this means

Error F9 indicates the inverter board that controls microwave power output has malfunctioned. The inverter allows the microwave to operate at variable power levels. When it fails, the microwave cannot produce any heat.

Step-by-step fix

3 steps
1

Power cycle

Unplug for 10 minutes and try again.

2

Test heating

Place a cup of water inside and try a 30-second cycle. If water stays cold, the inverter has likely failed.

3

Schedule professional repair

Inverter replacement involves high-voltage components and must be done by a qualified technician.

When to call a professional

Inverter replacement is a professional-only repair due to high-voltage components.

Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.

Learn more about our sources

Parts you may need

Inverter Board

Part #Model-specific · $80–$180

If inverter has failed

Find Part

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Quick Info

BrandKenmore
ApplianceMicrowave
Error CodeF9
DifficultyProfessional
Est. Time45–60 minutes