Oven shows E3 and does not heat correctly or shuts off during preheat

Safety first: Turn off power at the breaker. Allow the oven to cool fully before inspection.

Check airflow and vents:

• Ensure the oven is installed with proper clearance as specified in the Midea installation manual.
• Inspect front and rear ventilation openings for obstructions (foil, insulation, cabinets too tight).
• Remove any blockages and avoid covering vents with foil or panels.

Inspect thermal cutouts and cooling fan:

• Remove the rear cover to access the high-limit thermostat / thermal fuse and cooling fan motor.
• Test the high-limit thermostat for continuity with a multimeter. If open at room temperature, replace it.
• Check the cooling fan blades for obstruction and spin them by hand; they should move freely.
• Apply power and listen for the cooling fan during a brief test (reconnect power temporarily). If the fan does not run when the oven heats, the fan motor or its wiring is faulty.
• Replace the cooling fan motor if it does not operate or is noisy and slow.

If all safety devices and the fan are good, the main control board may be mismanaging temperature and should be evaluated or replaced by a professional.