Display shows U2 and the cooker beeps without starting, often related to lid status.

Safety first: Never force the lid closed if resistance is felt; check for obstructions.

• Match mode and lid state: For pressure programs, ensure the lid is fully closed and locked. For some non-pressure modes, the lid may need to be open; follow the manual.
• Check lid sensor: Open and close the lid firmly. Listen for the lock click and ensure the display changes state (if indicated).
• Clear previous errors: Unplug the cooker for a few minutes to reset any software lock, then try again.
• Inspect lid mechanism: Clean the lid latch and lock area. Remove any food debris that might prevent full closure.
• Sensor alignment (advanced): If the lid sensor is adjustable, ensure it aligns correctly with the lid magnet or actuator. Adjust or replace if necessary.