Microwave displays F9 and may shut off or refuse to start; sometimes associated with power issues.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Unplug the microwave before inspecting any wiring.
External checks:
- Verify the outlet is properly grounded and supplying correct voltage (typically 120 VAC in North America). Use a receptacle tester or multimeter if available.
- Avoid using extension cords or power strips; plug the microwave directly into a dedicated outlet.
Internal checks (for experienced DIYers):
- Remove the top grille and control panel to access the power input area.
- Inspect the power cord connection, terminal block, and wiring harness for loose connections or signs of overheating.
- Reseat any loose connectors.
Corrective action:
- If the home wiring or outlet is suspect, have a licensed electrician correct the issue.
- If internal wiring and the outlet are good, a failed control board power relay or other board component may be causing F9, requiring replacement of the electronic control board.
Note: Persistent F9 errors after verifying proper power supply should be diagnosed by a professional technician.
Repair Difficulty
Required Part
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