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HomeRepair HelpBosch Microwave RepairBosch Microwave is sparking or arcing Repair
Bosch Microwave is sparking or arcing
When your Bosch microwave is sparking, arcing, or making sparks when running, stop using it and unplug it before inspecting the oven. The most likely cause is a damaged or loose waveguide cover, which can burn or arc inside the oven cavity and should be replaced if it will not stay in place. If the microwave is sparking in the cabinet area, inspect the door switches for burn marks or damage, since a failed switch can short and create smoke or a burning smell. Arcing behind the waveguide cover may point to a damaged magnetron, while a visibly burned high-voltage diode can also cause cabinet-area sparking. Check interior shelf supports for burn spots, and inspect the cavity walls for chipped paint exposing bare metal. Sand and repair small damaged areas with microwave-safe touch-up paint. Replacing a magnetron or high-voltage diode requires work near the high-voltage capacitor, which stores a lethal charge even after the microwave is unplugged. Any repair requiring the outer cabinet to be removed requires proper capacitor discharge and may require a qualified technician if you are unfamiliar with the procedure. Enter your Bosch microwave model number to find the exact replacement waveguide cover, door switch, magnetron, diode, shelf support, or touch-up paint for your appliance.
01 - Bosch Microwave Waveguide Cover
The waveguide cover might be damaged and arcing or burning. If this is the case or if the cover will not stay in place, replace it with a new one.
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02 - Bosch Microwave Door Switch
If the microwave is sparking or arcing in the cabinet area, and not in the oven cavity, you will likely see smoke or there will be a burning smell. One of the appliance's door switches could have shorted and is causing the sparking or arcing. You should inspect each door switch for burn marks or damage and test the components with a multimeter to determine if any the door switches are malfunctioning.
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03 - Bosch Microwave Magnetron
If the microwave is sparking or arcing behind the waveguide cover in the oven cavity, you will likely see smoke or there will be a burning smell. The appliance's magnetron is one of the components that could be damaged and causing the sparking or arcing. Inspect the magnetron for burn marks or damage and replace if necessary.
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04 - Bosch Microwave Diode
If the microwave is sparking or arcing in the cabinet area, and not in the oven cavity, you will likely see smoke or there will be a burning smell. The appliance's diode is one of the components that could be damaged and causing the sparking or arcing. When the diode fails, it is often visibly burned out. Inspect the diode and if the diode is burned out, replace it. If inspecting the diode proves inconclusive, test it with a multimeter that uses a 9-volt battery or put a 9-volt battery in series with the diode. When the leads are reversed, the diode should only have continuity in one direction..
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05 - Bosch Microwave Shelf Support
Some microwave ovens will have cooking shelf supports on the interior walls. Inspect the shelf supports for any burnt spots or damage. If there are any burnt or damaged spots, replace with new supports as needed.
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06 - Bosch Microwave Touch-Up Paint
The paint on the interior of the microwave might be chipped. If the paint is chipped, the interior metal will be exposed, causing the microwave to spark or arc. Check the interior of the microwave for any spots where the paint has chipped away. If there are any damaged spots, gently sand the compromised area and touch them up with microwave oven interior paint.
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Frequently Asked Questions
Why is my Bosch microwave sparking inside?
Why is my Bosch microwave sparking in the cabinet area?
Can I keep using my Bosch microwave if it sparks or smells burnt?
How do I test a Bosch microwave diode or door switch?
How do I find the correct Bosch microwave waveguide cover or other replacement part?
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