Oven fan runs but no heat; error indicates relay or power stage fault.

Safety first: Turn off power at the breaker. Capacitors on the control board can retain charge; avoid touching components unnecessarily.

• Verify element and sensor first: Confirm that bake/broil elements and the temperature sensor are functional. If they are good, focus on the control board.
• Access the main control board: Remove the top or rear panel (depending on model) to expose the PCB. Take clear photos of wiring before disconnecting anything.
• Inspect for damage: Look for burnt areas, cracked solder joints under the heater relays, or melted connectors. Any visible damage usually means the board must be replaced.
• Check relay operation (advanced): With power restored and extreme caution, a technician can measure output voltage from the relay to the element when a heating mode is selected. If the relay never closes despite a call for heat, replace the board.
• Replace the control board: Label and disconnect all connectors, remove mounting screws, install the new Bertazzoni-compatible PCB, and reconnect wiring exactly as before.