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HomeRepair HelpLG Microwave RepairLG Microwave is sparking or arcing Repair
LG Microwave is sparking or arcing
When your LG microwave is sparking, arcing, or making sparks and pops when running, stop using it and inspect the oven before operating it again. The most likely cause is a damaged or loose waveguide cover, which can cause microwave waveguide cover sparking or burning inside the cavity. Next, check the door switches for burn marks or damage, especially if arcing occurs in the cabinet area with smoke or a burning smell. A damaged magnetron or burned high-voltage diode can also cause microwave sparking inside, particularly behind the waveguide cover. Less common causes include burnt shelf supports or chipped interior paint that exposes metal and creates an arc. Replace damaged supports or use approved microwave touch-up paint for small interior paint defects. Testing or replacing a door switch, high-voltage diode, or magnetron may require opening the outer cabinet. The high-voltage capacitor stores 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 repair. Enter your LG microwave model number to find the exact replacement waveguide cover, door switch, magnetron, diode, or other part for your specific appliance.
01 - LG 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 - LG 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 - LG 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 - LG 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 - LG 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 - LG 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 LG microwave sparking inside?
Is a microwave that is sparking dangerous?
How do I test an LG microwave door switch or diode?
Should I replace the magnetron if my LG microwave is sparking?
How do I find the correct LG microwave waveguide cover or door switch?
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