F4

Magic Chef Thermal Cutout or Overheat Protection Error

Microwave shows F4 and may not start or may stop during operation.

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

Open thermal cutout on magnetron, Open cavity thermal fuse, Blocked ventilation, Failed cooling fan

How to Fix / Troubleshooting

Safety: Unplug the microwave and let it cool completely.

Ventilation check:

Ensure all external vents are clear and that the unit has proper clearance.
Clean grease filters and any accessible intake screens.

Internal inspection:

Remove the outer cabinet and locate thermal cutouts/fuses on the magnetron and cavity.
Test each thermal cutout with a multimeter for continuity. An open reading at room temperature indicates a blown device (unless it is a resettable thermostat that has not reset).
Check the internal cooling fan for proper operation and free movement.

Corrective actions:

Replace any open thermal cutout or thermal fuse with the exact Magic Chef-specified part.
Replace a failed cooling fan motor.
Address any airflow obstructions or installation issues that caused overheating.

Repair Difficulty

Hard 4/5

Required Part

Thermal Cutout

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