What to Check First
- Check if there is food residue inside the oven. Food particles can become carbonization and cause sparks. If any food particles are present, clean them away and retry using the microwave.
- Examine cookware being used Bowls or plates with gold or silver lined patterns will begin to spark when the microwave is in use. DO NOT place aluminum or metal like items in the microwave as they will cause sparking and damage the microwave. Use only microwave safe heat-resistant cookware.
- Examine the microwave rack (applicable models) If the unit came with a metal rack, be certain that the rack is installed properly and all four of the plastic support brackets are in place and undamaged.
- Arcing or sparking occurring inside of the microwave oven’s cavity can be caused by overcooked food spills, improper cookware, or damage to the oven cavity.
- Food particles can become carbonization and cause sparks. If any food particles are present, clean them away and retry using the microwave.
- Bowls or plates with gold or silver lined patterns will begin to spark when the microwave is in use. DO NOT place aluminum or metal like items in the microwave as they will cause sparking and damage the microwave. Use only microwave safe heat-resistant cookware.
- If the unit came with a metal rack, be certain that the rack is installed properly and all four of the plastic support brackets are in place and undamaged.
- If the plastic support brackets are damaged, or the microwave continues to spark, service will be required for a proper diagnosis. Please visit our Request a Repair page for further assistance.
Why This Can Happen
Symptoms can have more than one cause, and the correct steps depend on the exact model, installation and operating conditions. Use the checks above to narrow the issue before service.
Safety and Model-Specific Guidance
Frequently Asked Questions
What should I check first for LG Microwaves - How to Prevent Sparking?
Check if there is food residue inside the oven. Food particles can become carbonization and cause sparks. If any food particles are present, clean them away and retry using the microwave.
When should I stop troubleshooting and contact LG?
Stop if the product shows signs of electrical damage, burning, leaking near electrical components, or if the recommended checks do not resolve the issue. Use LG USA support for model-specific service guidance.
Does this guidance apply to every LG model?
Not always. Controls, error codes and service steps can differ by model. Confirm the exact model number and follow the linked LG USA article for model-specific instructions.
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