Display shows E3 and the unit will not start or shuts down; fan may still run briefly.

Safety first: Unplug the air fryer before any inspection. Do not operate the unit on an unstable or questionable power source.

Step-by-step checks:

• Verify outlet: Plug another small appliance (like a lamp) into the same outlet to confirm stable power. Avoid using long or undersized extension cords or power strips.
• Try a different outlet: Move the air fryer to a known-good outlet on a different circuit, preferably without other heavy loads (microwave, toaster oven) running simultaneously.
• Inspect the power cord: Check the entire length of the GoWISE USA power cord for cuts, kinks, or burn marks. If damaged, do not use the unit.
• Internal connection check (advanced): With the unit unplugged, remove the bottom or rear cover to access the internal power cord connection and terminal block. Ensure all screws are tight and wires are firmly seated with no discoloration.
• Control board inspection: Look at the main control board for burnt components, bulging capacitors, or scorch marks. Any visible damage usually means the board must be replaced.

When to stop: If E3 persists on multiple outlets and there is no obvious cord damage, the internal power supply on the control board is likely faulty. Replacement of the main control board should be done by a qualified technician.