You most likely have a backlight issue with this TV set. Could be the inverter circuits for the backlights. The inverter is the power supply source for the backlights. there could also be a screen driver problem. This would entail changing the entire board. You should call in an authorized LG repair center to check this set out for you. Good Luck and please let us know what you found out about this TV set.
"Those who do not know their opponent's arguments, do not completely understand their own".
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