Display shows E3 during preheat or cooking; unit may shut off or refuse to start a new cycle.

Safety first: Unplug the air fryer and allow it to cool for at least 45 minutes. Overtemperature faults can mean very hot internal components.

• Check ventilation: Ensure the Crux air fryer has at least 5 inches (12 cm) of clearance on all sides and is not placed under cabinets or against a wall. Clear any obstructions from the rear exhaust and bottom intake vents.
• Clean interior and heater area: Remove the basket and drawer. Carefully wipe away grease and food debris from the heater guard and interior walls. Built-up grease can trap heat and trigger E3.
• Inspect fan operation: Start a cycle with an empty basket (if the unit will run). Listen for the fan. If the fan is not running or sounds weak, shut off and unplug immediately; a failed fan motor can cause overheating.
• Check thermal cutoff and sensor (advanced): With the unit unplugged and opened, locate the thermal cutoff/thermal fuse near the heater and the NTC sensor. Test continuity of the thermal fuse with a multimeter; if open, it must be replaced with the same temperature and current rating. Verify the sensor is firmly attached to its mounting point and not hanging loose.
• After repair: Reassemble, ensure vents are clear, and run a short test cycle at a moderate temperature while monitoring for normal operation.