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

Safety: Do not repeatedly reset the breaker; this can be dangerous.

Steps:

• 1. Try another outlet: Plug the microwave into a different, properly rated circuit (if possible) to rule out a weak breaker. Do not use extension cords.
• 2. Observe when it trips: If the breaker trips immediately when START is pressed, a high-voltage short is likely. If it trips after some time, overheating or overload may be involved.

Because this symptom strongly suggests a shorted high-voltage component, internal diagnosis should be left to a professional technician. Continued use can damage wiring and pose a fire risk.