Oven display shows F05 and the cooling fan runs continuously or not at all.

Safety first: Disconnect mains power before removing any panels. Sharp metal edges may be present; wear cut-resistant gloves.

• Check fan operation: After restoring power briefly, start a low-temperature program and listen for the cooling fan (usually above the oven cavity, behind the control panel). If it is noisy, intermittent, or not running, switch power off again.
• Access the fan: Remove the top cover or rear panel of the cooker to expose the tangential cooling fan assembly.
• Inspect for obstruction: Ensure no insulation, wiring, or debris is fouling the fan blades. Spin the fan by hand; it should rotate freely without grinding.
• Test the motor: Disconnect the fan motor and measure resistance across its terminals. An open circuit indicates a failed motor. If comfortable and safe, you can also bench-test the motor with the correct mains voltage using insulated leads.
• Check wiring and relay: Inspect the harness from the control board to the fan for breaks or heat damage. On the control board, listen for the fan relay clicking when the oven is started; absence of a click may indicate a faulty relay.
• Replace components: Replace a seized or open cooling fan motor. If the motor and wiring are good but F05 persists, the control board fan relay or driver circuit may need replacement by a technician.