E4 appears on the display and the cooker will not start or stops mid-cycle.

Safety first: Unplug the unit and ensure it is completely depressurized and cool before working near the lid or steam vent.

• Clean the steam release and lid: Remove the steam release valve (if removable) and clean it under warm water. Clear any food particles from the vent path. Clean the underside of the lid, especially around the sensor area.
• Inspect lid wiring: Open the lid and look at the hinge area where wires pass through. If the insulation is cracked or wires are pinched, the sensor signal may be intermittent.
• Check lid sensor connector: On some Bella models, the lid sensor plugs into a small connector near the hinge or under the top cover. With the unit unplugged, gently reseat this connector.
• Test operation: Reassemble and try a low-temperature program (e.g., Keep Warm). If E4 appears immediately, the lid sensor is likely defective.
• Replace lid sensor assembly: If accessible, remove the screws securing the inner lid panel to access the sensor. Replace the lid temperature sensor or lid sensor harness with a compatible Bella part.