Microwave emits sparks or arcing inside the cavity during cooking.

Immediate action: Press STOP and unplug the microwave as soon as you see sparks.

Steps:

• Remove metal objects: Ensure no metal utensils, foil, or twist ties are inside.
• Inspect waveguide cover: Locate the small mica waveguide cover on the side or top interior wall. If it is burned, cracked, or has holes, it must be replaced.
• Clean cavity: After cooling, clean the interior thoroughly with mild detergent and water to remove grease and burnt food, especially near the waveguide cover.
• Replace waveguide cover: Order a compatible Clatronic waveguide cover and install it according to the manual (usually held by one or two screws or tabs).

Warning: Do not operate the microwave with a damaged or missing waveguide cover; this can damage the magnetron.