The motor has a mechanical, centrifugal switch, that engages a “start winding” until the motor overcomes the initial torque and starts spinning. I think in your case, the switch is going bad or needs lubrication. It “buzzes” because it is not fully engaging and the motor won’t spin up. If you were to literally “kick” the base of the dryer (don’t dent it!), you might actually cause enough vibration to ‘reset’ the mechanical switch inside the motor. If that works, it’s the switch. (Have some fun!)
Here’s an excellent video on a total motor replacement, that gets you to the motor to either try a repair or replace it. At this point, I do not recommend a motor replacement, as the symptom tells me the motor is working, just not starting correctly.
https://youtu.be/cc1HZzBMpzk?feature=sha...
As he pulls the motor out, pause the video. (5:07)
The centrifugal switch is seen, down inside the motor frame, around the shaft.
Below is a second video, explaining the motor itself and possible troubleshooting and repair. Please do not attempt any repairs with the dryer plugged in, the 220V circuits can be deadly. If you open your dryer up (the first video has excellent steps), you might be able to lubricate the centrifugal mechanism to ‘unstick’ it and provide free movement.
https://youtu.be/fhZsqzU1hzQ?feature=sha...
This is a generic explanation, not the LG dryer, but it shows how the mechanism works. Spray it with a light lubricant (WD40 or LPS) and move it back and worth with a screwdriver (unplugged from the wall!!). You can reassemble the dryer without the drum and belt, to be able to plug it back in and start the motor, to watch the engagement (you must force the belt switch to the ‘ON’ position with tape or string. Be very careful, after you replug to the wall. You should hear the switch “click” as the motor starts, using the front panel to start and stop, multiple times to ensure it engages freely. Unplug from the wall and put the drum and belt back in place, removing your belt switch “jammer”, and try it out.
Good luck and I hope you save money fixing it yourself. Wear your badge of self repair proudly!
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