LG LMV1813ST MIRCOWAVE STOPPED WORKING?

Could be magnetron failure but cooking a "foreign" object may have led to breakdown

The service manual for your model is here. That and my video here will give you disassembly info.

More questions? Contact me directly here.*

* always include the full model number and FCC ID number from the label on / in your microwave

The door switch and fuse will stop it from running.

If there was any odor, the cloud might have come from a failed component, such as the high voltage rectifier. That could blow the fuse.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/david_29ad5d1dd86564b0

If too much current passes through the microwave circuitry, the line fuse will blow. If the line fuse blows, the microwave won't start. To determine if the line fuse is at fault, use a multimeter to test it for continuity. If the fuse does not have continuity, replace it. In addition, you should investigate and resolve the problem that caused the fuse to blow. If you don't resolve the underlying issue, the new fuse will blow too. (Caution: The microwave oven can store thousands of volts of electricity in its high voltage capacitor, even after the microwave oven has been unplugged. Due to the potential for electric shock, it is extremely dangerous to replace the electronic components in a microwave. Only a licensed technician should replace the line fuse.)

replacemotor under microwave

Go for a warranty repair anyway. It may be the magnetron, and the clicking is the big condenser discharging.
https://www.lg.com/ca_en/support/warranty
Microwave Ovens (Over-the-Range):

• 1 year parts & labour
• 5 years on the magnetron (part only)

Microwave Ovens (countertop):

• 1 year replacement warranty
• 5 years on the magnetron (part only)

Our LG did the same thing - called customer service and they told us the open and slam the door 10 times. It actually worked! It reset the switches somehow.