Microwave shows F8 and may shut down during operation, especially at high power.

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

Low or high incoming line voltage, Loose power cord or internal connections, Failing line filter board, Control board sensing circuit fault

Safety first: Unplug the microwave.

External checks:

Test the wall outlet voltage (ideally 110–120V AC in North America) using a proper meter or have an electrician check.
Avoid using extension cords or power strips; plug directly into a dedicated outlet.

Internal checks:

Inspect the power cord entry, line filter board, and wiring for loose connections or burn marks.

If F8 continues with proper line voltage and secure connections, the control or line filter board may need replacement by a technician.

Hard 4/5

Line Filter Board

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