E4 appears shortly after starting a pressure or high-heat program; cooker stops heating.

Safety first: If the unit is under pressure, do not attempt to open the lid until pressure is fully released according to the manual. Unplug the cooker.

• Release pressure safely: Use the designated steam release control to vent pressure away from your body. Keep hands and face clear of the steam path.
• Clean the lid components: Remove the steam release cap, anti-block shield, and silicone cap (if present). Wash them in warm soapy water, rinse, and dry thoroughly. Ensure all steam passages are clear.
• Check food thickness: Very thick sauces, chili, or starch-heavy dishes can trap heat. Add more liquid and avoid filling above the recommended maximum for such foods.
• Inspect the bottom of the pot: Remove any stuck or burnt food. A scorched layer can cause localized overheating.
• Test on a simple recipe: After cleaning, cook plain water or a thin soup to see if E4 returns.

Persistent E4 with clean vents and proper recipes may indicate a failing thermal cutoff or sensor on the heater assembly, which should be replaced by a professional.