What to Check First
- If operating the microwave while empty, sparking may occur. An item such as food or water needs to be in the unit in order to absorb the microwaves emitted from the wave guide, otherwise the cavity could be burned or scorched. Place a 8 oz. cup of water in the microwave and run a TIMED COOK for 30 seconds. If no sparking or arcing occurs, it is okay to continue use.
- Only microwave safe cookware, containers, and utensils should be used in the microwave oven. Failure to follow these guidelines may result in such items sparking. This includes metal utensils, wire twist ties, etc.
- If the microwave comes with a metal rack, be certain that the rack is installed properly on all four of the support brackets. If not, sparking can occur. The brackets are plastic to prevent sparking from happening when installed properly. If the rack is not installed properly and the it touches the wall inside the microwave, sparking will occur.
- If the microwave hasn't been cleaned for a while, food crumbs and spill overs can overcook and cause sparking. Clean any food spills immediately and keep the interior of the unit clean. After cleaning, check to be sure there hasn't been any damage to the interior of the cavity before continuing use.
- If the interior of the cavity has been damaged, arcing and sparking can occur. Discontinue use of the microwave, the unit will require repair service .
- If there is arcing or sparking occuring inside the microwave oven's cavity, certain things should be checked to potentially resolve the issue:.
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 Microwave: Why is my Microwave Arcing or Sparking??
If operating the microwave while empty, sparking may occur. An item such as food or water needs to be in the unit in order to absorb the microwaves emitted from the wave guide, otherwise the cavity could be burned or scorched. Place a 8 oz. cup of water in the microwave and run a TIMED COOK for 30 seconds. If no sparking or arcing occurs, it is okay to continue use.
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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These model pages are linked because the stored category or exact model matches this Help Library topic.
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