Smeg oven displays Er09 and lower heating element does not work.

Safety first: Disconnect mains power and let the oven cool.

• Access bottom element: Remove oven shelves and the bottom panel inside the cavity to expose the lower element (if internal). Some models have the element hidden under the cavity; access from the rear panel may be required.
• Inspect for damage: Look for cracks, bulges, or burn marks on the element. Any visible damage means the element should be replaced.
• Test with multimeter: Disconnect the element leads and measure resistance. An open circuit indicates a failed element. Replace with the correct Smeg bottom element.
• Check wiring and board: If the element is good, inspect the wiring back to the main control board. If wiring is intact, the board's relay/triac for the bottom element may be faulty and require replacement.