Recheck the ribbons at the T Con board. Make sure they’re clean and fully seated. T con maybe failing. Use rubbing alcohol to clean and let them fully dry before reconnecting.
I have an LG 49UF680V and the screen started to flicker lines, then one half went black and the other flickering white. I reseated ribbon wire within the TV, which stopped the flickering, but now the problem I have is: the TV turns on, the backlights light up, but there is no sound or picture. I can't bring up the menu or change the source. I have changed the input port, changed the HDMI wire and unplugged the TV overnight but still no good.
Has anyone got any useful tips or tricks to solve this at home, I don't fancy buying a new TV right now.
Thanks,
MD

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