Safety first: Disconnect mains power. Cooling fans are near live wiring and sharp metal edges.

Check for airflow: During normal operation, warm air should exit above the oven door or at the front vent. If no airflow is felt when the oven is hot, suspect the cooling fan.
Access the cooling fan: Remove the oven from the cabinet if necessary. Take off the top cover to access the cooling fan assembly.
Inspect fan blades and motor: Look for obstructions (insulation, wiring) preventing rotation. Spin the fan by hand; it should turn freely. If seized or noisy, replace the cooling fan motor assembly.
Electrical tests: With power disconnected, check continuity of the fan motor windings. If open, replace the motor. Also check any inline thermal fuse in the fan circuit.
Control output: If the fan motor is good but never receives voltage (or runs constantly), the control board's fan driver (relay/triac) may be defective and require replacement.

Proper cooling is critical to protect electronics; do not operate the oven with a faulty cooling fan.

Cooling fan runs at full speed constantly or does not run at all; oven may shut down with error during use.

Possible Causes