Microwave stops heating shortly after start; display shows E02 and beeps.

Safety first: Unplug the microwave before inspection. Do not remove the outer cabinet unless you are a trained technician; high-voltage components inside can be lethal.

User-level checks:

• 1. Check ventilation: Ensure the microwave has at least the clearance specified in the Breville manual (typically several centimeters on sides, top, and rear). Move it away from walls or cabinets if airflow is restricted.
• 2. Clean vents: Inspect the side, rear, and underside vents. Use a soft brush or vacuum to remove dust, grease, or lint blocking airflow.
• 3. Avoid running empty: Make sure you always run the microwave with food or a microwave-safe load inside. Running empty can overheat the magnetron and trigger E02.
• 4. Cool-down period: Allow the unit to cool for 20–30 minutes unplugged, then plug back in and test with a cup of water for 1–2 minutes.

Technician-level checks:

• Verify operation of the magnetron cooling fan motor during cooking.
• Test the magnetron thermal cut-out (thermal fuse/thermostat) for continuity.
• Inspect the magnetron for signs of overheating or arcing.

If E02 recurs after ensuring proper ventilation and cleaning vents, discontinue use and contact a qualified technician. Continued operation may damage the magnetron.