Visible sparks or arcing inside the microwave cavity during cooking.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Stop the microwave immediately by pressing Stop/Cancel and opening the door. Unplug the unit.
- Remove metal objects: Take out any metal utensils, foil, twist ties, or containers with metallic trim. Bosch microwaves should not be used with metal unless specifically designed accessories are provided.
- Inspect waveguide cover: Check for burn marks or holes. Replace if damaged.
- Check cavity paint: Look for chipped paint or rust spots where bare metal is exposed. These areas can cause arcing.
- Use proper cookware: Only use microwave-safe glass, ceramic, or plastic containers without metallic decoration.
If arcing continues with proper cookware and intact waveguide cover: The cavity coating or internal components may be compromised. Have the unit inspected by a Bosch technician.
Repair Difficulty
Required Part
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