E4 error appears and the unit refuses to start or aborts mid-cycle.

Safety first: If the cooker is hot, keep hands and face away from the steam release area. Unplug the unit and allow pressure to release naturally before disassembly.

• 1. Inspect steam release valve: Remove the steam release cap from the lid (if removable on your Chefman model). Clean any food debris or starch buildup. Ensure the valve moves freely.
• 2. Clean float valve and anti-block shield: Remove the anti-block shield (small metal or plastic cover under the lid) and clean it thoroughly. Check that the float valve pin moves up and down freely and is not stuck with dried food.
• 3. Check lid lock switch: With the unit unplugged, open and close the lid while listening for a faint click from the lid lock microswitch. If there is no click or the lid feels loose, the switch or latch may be misaligned or broken.
• 4. Inspect pressure sensor (advanced): Some Chefman multicookers have a pressure sensor connected via a small silicone tube to the lid or inner chamber. Ensure the tube is not kinked, blocked, or disconnected. Clean any moisture or residue from the sensor port.
• 5. Test with water only: After cleaning, add 2 cups of water and run a short pressure cycle. If E4 clears, the issue was likely blockage. If it persists, the pressure sensor or lid lock assembly may need replacement.

Never attempt to bypass the pressure sensor or lid lock; these are critical safety components.