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HomeRepair HelpWhirlpool Microwave RepairWhirlpool Microwave is sparking or arcing Repair
Whirlpool Microwave is sparking or arcing
If your Whirlpool microwave is sparking or arcing, stop using it and unplug it before inspecting the oven. The most likely cause is a damaged, burned, or loose waveguide cover, also called a mica sheet. Replace the cover if it will not stay in place. If the microwave sparks inside the cabinet area rather than the oven cavity, a failed door switch, including the primary door switch, secondary door switch, or monitor switch, may be shorting. Check for burn marks and test the switches with a multimeter. Sparking behind the waveguide cover can also indicate a damaged magnetron, while a visibly burned high-voltage diode may cause arcing in the cabinet. Less common causes include burned shelf supports or chipped interior paint that exposes the metal cavity. These repairs may require opening the outer cabinet. The high-voltage capacitor can store a lethal charge even after the microwave is unplugged, so it must be properly discharged before interior work. If you are not familiar with capacitor discharge procedures, have a qualified technician handle the magnetron, high-voltage diode, or other high-voltage repairs. Enter your Whirlpool microwave model number to find the exact replacement waveguide cover, door switch, magnetron, diode, shelf support, or touch-up paint for your appliance.
01 - Whirlpool 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 - Whirlpool 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 - Whirlpool 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 - Whirlpool 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 - Whirlpool 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 - Whirlpool 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 Whirlpool microwave sparking inside?
What should I check if my Whirlpool microwave sparks and smells like burning?
Can I test the Whirlpool microwave door switches or diode with a multimeter?
Is a Whirlpool microwave that sparks or turns on with the door open dangerous?
How do I find the correct Whirlpool microwave waveguide cover or door switch?
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