Microwave produces visible sparks or arcing inside when heating certain foods or containers.

Safety first: Stop the microwave immediately if you see sparks.

• Remove inappropriate items: Do not use metal containers, foil, or dishes with metallic trim in your Telefunken microwave.
• Clean thoroughly: Remove all food splatters and grease, especially near corners and the waveguide cover.
• Inspect cavity coating: If paint is chipped and metal is exposed, apply microwave-safe touch-up paint after cleaning and drying.
• Replace waveguide cover: If the cover is burnt or cracked, replace it before further use.