HE identifies a heater fault in documented LG models. Noting whether it occurs during wash or dry helps narrow the inspection, but it does not identify a heating element to replace.
The LG front panel distinguishes HE from tE and dHE. Copy the full code before turning off the unit and note which function was active.
A reset has a limited scope
If the manual allows a restart and there is no unusual odor, leak, or visible damage, follow that specific reset procedure. If HE disappears, it only means the alarm stopped showing during that attempt. If it returns, the fault is not solved by repeating the same cycle.
Do not test at maximum temperature or open the appliance to check wires or heating elements. Also avoid touching the door or removing hot laundry from a drum that is still locked; wait for the expected cooling and release.
If the machine combines washing and drying, tell service whether the wash had finished and whether it was heating for drying. That context lets them check the corresponding circuit for the installed model.
If HE repeats, heating and control need to be checked; save the code and stop using thermal functions until you receive instructions.