Microwave stops heating shortly after start; display shows E02 and may beep repeatedly.

Safety first: Unplug the microwave. Internal components can store high voltage; do not touch the capacitor or high-voltage wiring. If the unit smells burnt or shows signs of melting, discontinue use and call a technician.

Basic user checks:

• 1. Check ventilation: Ensure the rear, sides, and top vents are not blocked by cabinets, walls, or items stored on top. Westinghouse microwaves typically require several inches of clearance around vents.
• 2. Clean intake and exhaust grills: Use a vacuum with a brush attachment to remove dust and grease from the vents. Grease buildup can cause overheating.
• 3. Test with a water load: Place a large microwave-safe mug of water inside and run on HIGH for 2–3 minutes. If E02 appears quickly, the cooling system may not be working.

Advanced checks (technician recommended):

• 4. Inspect cooling fan: With the cover removed (by a qualified person), verify the fan motor spins freely and runs when the unit is started. Replace the fan motor if seized or not powered.
• 5. Test thermal cutouts/fuses: Locate the cavity thermal fuse and magnetron thermal cutout on the cavity and magnetron. Test for continuity with a multimeter. Replace any open (blown) device with the correct Westinghouse-rated part.

If the unit repeatedly overheats or blows thermal devices, there may be a deeper issue with the magnetron or control board; professional diagnosis is advised.