Oven display shows E05 and the cooling fan runs continuously or not at all; oven may shut down unexpectedly.

Safety first: Disconnect mains power. The cooling fan area has sharp metal edges; wear cut-resistant gloves.

• Check for airflow obstruction: Ensure the oven is installed with proper ventilation clearances as per the manual. Remove any items blocking the top or rear vents.
• Access the cooling fan: Remove the top cover or rear panel (depending on model) to expose the cooling fan assembly above or behind the oven cavity.
• Inspect the fan: Try spinning the fan blades by hand (with power off). They should rotate freely without grinding. Clean dust and grease from the blades and housing.
• Test the fan motor: Disconnect the fan motor connector and measure resistance across the motor terminals. An open circuit indicates a failed motor. Also check for signs of overheating or melted insulation.
• Check wiring and board: Inspect the harness from the fan to the control board for damage. If the motor and wiring are good, the fan driver (triac/relay) on the PCB may be defective, requiring board replacement.