• ** REMEMBER! **The microwave can still shock you even unplugged!!

    ALWAYS discharge the high-voltage capacitor first if you even think your hands will come close to any HIGH VOLTAGE components.

    Jeff mentions this: Anything in the high voltage ( magnetron, capacitor, diode, wires to and from ):
    ...Use a metal ( not the shiny chrome type ) screw driver with a insulated handle to short across ( touch both at the same time ) the terminals of the high voltage capacitor to discharge it.

    From Jeff's site: http://www.applianceaid.com/component-testing.php

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LG microwave LMC2075ST turns on and runs but wont heat


Feb 15, 2023
Model Number
1-5 years
I checked all the door switches and they seem to open and closing the circuit.
Unfortunately, I don’t have a schematic on your model. Can you provide the FCC ID number from the label in the door? Your microwave has three switches. With the door open, two have continuity and one does not. Door closed, one has continuity and two do not. Test the feel of the switches as well. If the microwave runs and is not heating AND switches test good, it is likely one of the thermal fuses, the diode, capacitor or magnetron. These are in the high voltage compartment and are very dangerous even if unplugged. Any strange or different sounds? LG thermal fuses are usually in line and when bad, there will be No power. So that likely narrows it down to the HV section.
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If your LG microwave (LMC2075ST) runs but doesn't heat, check the power level, and timer settings, and ensure the door is securely closed. Test it at different power levels and durations to rule out user settings. If the issue persists, it may be a problem with the microwave's magnetron, capacitor, or diode, which would require professional diagnosis and repair. Safety precautions should be taken, as microwaves can contain high-voltage components even when unplugged.

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