Chosen Solution

Same problem here unplugged did hard and factory reset.turns on shows time and lg logo front red light goes dark screens goes very dim but can still see and use nav menu and tv plays sound.please help im thinking led strip or power board hope its something easier than these options Update (10/23/2022) Sorryy its an LG 55LM5850-UF 3d. Tv. Also with. Cover off ppowerboard blinks 4 yellow/orange over and over. Pictures too come

picture of my board === ===

@petercw we would need to know the exact model of your TV. It is an LG and they do have trouble with the backlight array (subpar quality strips being used). Of course, you do want to check the voltages from your power supply to the backlight LED’s. For that you would have to remove the back cover and test the DC voltages. If you take some good pictures of your boards and post those with your question, we could most certainly point you to where to test and what to expect. Adding images to an existing question