Microwave trips the household circuit breaker or blows a fuse when starting a cook cycle.

Critical safety warning: Repeatedly resetting a tripping breaker can be dangerous. Do not continue to use the microwave until the cause is identified.

Steps:

• Test outlet with another device: Confirm the circuit can handle other loads without tripping.
• Try a different outlet: If possible, plug the microwave into another properly rated outlet on a different circuit to rule out wiring issues (do not use extension cords).
• Observe when it trips: If the breaker trips immediately when pressing Start, a short in the high-voltage system or line filter is likely.

Next steps:

• Stop using the microwave and contact a qualified technician.
• The technician will test the high-voltage capacitor, diode, magnetron, and line filter for shorts and replace the defective component.