Smeg oven trips the circuit breaker or RCD when turned on or when a specific function is selected.

Safety first: Do not repeatedly reset a tripping breaker. Disconnect the oven and investigate before further use.

• Identify function causing trip: Note whether the trip occurs immediately when selecting grill, fan bake, etc. This helps pinpoint the faulty circuit.
• Insulation test (if equipped): Use an insulation tester (megger) between each element terminal and earth. Low resistance indicates leakage; replace the affected element.
• Inspect wiring: Remove the rear panel and inspect all wiring for cuts, burns, or pinched sections touching the metal chassis. Repair or replace damaged wires.
• Check mains filter: Inspect the mains interference filter near the terminal block for signs of burning or cracking. Replace if suspect.
• Dry out moisture: If the issue started after cleaning or a spill, allow the oven to dry thoroughly with power disconnected for 24 hours, then retest.