Oven fan runs but no heat, or intermittent heating, with E3 displayed during operation.

Safety first: Disconnect mains power. Capacitors on the control board may retain charge; avoid touching bare conductors.

• Access control PCB: Remove the top or side cover (depending on model) to reach the electronic control module behind the front panel.
• Visual inspection: Look for darkened areas, burnt smell, or cracked solder joints around the heater relays or triacs. Check for loose spade connectors on the board.
• Mechanical test: In some models you can gently tap the relay body (with power disconnected) and look for signs of mechanical damage or loose casing.
• Electrical test (advanced): With the board removed, use a multimeter to check continuity across relay contacts when manually energized (if you have a bench supply) or check for shorted triac terminals. This step is recommended only for experienced technicians.
• Replace control board: For most home users, the practical repair is to replace the entire Clatronic oven control module with the exact part number. Transfer any wiring harnesses one by one to avoid misconnection.
• Recalibration: Some models may require a temperature calibration or reset after board replacement; follow the user or service manual.