Hi everyone picked up this 75inch lg tv has sound but no picture. So far I have disconnected each lvds cable separately from the t con with no change in picture. I have looked at the boards with a thermal camera and the hottest component is the one pictured. I can’t seem to find any information on it online.
75um7050pla have backlight no sound
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Suppose its a double diode, testing there, hes on a double at the 7:40 mark, meter set to diode mode: https://www.youtube.com/watch?v=0VfSvU1AHfc -
One possibility and something that should be watched out for, is maybe someone ordered the wrong mainboard. What can happen is they may order by the silkscreen numbers on the board instead of the numbers on a sticker that is usually on every board AND like our old pal Budm always stated "The silkscreen numbers are just the indicator of the board used before it is populated with other components, once it gets populated it gets the sticker which identifies the specifics of the board"Comment
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Thanks, Yes quite possible, is there a way of checking the screen before I replace any of the boards?
I have disconnected the ribbon cables one at a time with no change to the display but as the above comment stated this is not the correct procedure for an LG.
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We just had a thread with what seems like the same problem, he had a double diode problem, a replacement mainboard fixed the issue, mainboards are tricky and complicated, even some seasoned pros can't figure them out.Comment
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show us please the U ribbon cable you tried to disconnected..!Comment
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