E4 appears and the cooker stops heating, often during pressure cooking or sauté mode.

Safety first: Disconnect power and allow the cooker to cool completely.

• Dry the interior: If you recently cleaned the cooker or had a boil-over, moisture may have entered the sensor area. Remove the inner pot and gently wipe the heating plate and surrounding area dry. Leave the lid open for several hours to air dry.
• Inspect sensor wiring: Remove the bottom cover and locate the NTC sensor wires. Check for crushed, pinched, or melted insulation that could cause a short. If you find damaged insulation, the sensor harness should be replaced.
• Check connectors: Unplug the NTC connector from the main PCB (with power disconnected), inspect for moisture or corrosion, and clean with contact cleaner. Let it dry fully before reconnecting.
• Test operation: Reassemble the base, add water to the inner pot, and run a low-temperature program. If E4 reappears quickly, the NTC sensor or control board is likely defective.

Warning: Do not attempt to measure live voltages inside the cooker unless you are trained and using appropriate insulated tools.