Microwave interior is sparking or arcing during cooking, especially near the waveguide cover or metal objects.

Immediate action: Stop the microwave immediately and unplug it if you see sparks or arcing.

Inspection:

• Remove any metal objects, twist ties, or foil from the cavity.
• Inspect the waveguide cover (usually a small mica or plastic panel on the side wall) for burns, holes, or heavy grease buildup.
• Check the cavity walls and ceiling for chipped or missing paint exposing bare metal.

Corrective action:

• Clean the cavity thoroughly to remove grease and food splatter.
• Replace a damaged waveguide cover with the correct Maytag part.
• Touch up small paint chips with microwave-safe cavity paint as recommended by the manufacturer.

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