LG 75UN8570AUD panel issue fixed with tape.

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  • triplefour
    Badcaps Legend
    • May 2014
    • 1747
    • USA

    #1

    LG 75UN8570AUD panel issue fixed with tape.

    I've been seeing a lot of the new TVs (samsung and LG only i think) maybe 1-2 years old suffering from sudden panel death and have been over 50% successful bringing them at least most of the way back to functionality if not all the way, with the tape masking of the LVDS pins method.
    add this one to the list. the issue was on the left side of the panel and i ended up blocking just 3 pins on the connector that joins the two panel boards that make up the left side of the panel (it has 4 boards total) i didnt get the picture back to 100% perfect. i spent hours fiddling with which pins to block before i settled on 12,13,14 (according to whatever way i was looking at it)
    on the way to finding the right pins to block i was seeing a picture with horizontal lines in it, washed out color, ticking between perfect color and washed out color rhythmically every few seconds, same rhythmic ticking but just changing the brightness a little... it seemed like every time i got close to perfect there was still some annoyance hanging around. i finally was able to get the picture stable with no ticking, and MOST of the color back but still a bit dingy. no horizontal lines tho. when watching a movie you can barely tell.

    https://youtu.be/XrQNiqBnlPc
    https://youtu.be/a4PoC0979EI

    i cant help thinking i could have got it perfect somehow...but i think i need better tape. thinner, stronger...tinted with some color... and a better setup for cutting it. the way ive been doing it i cut what looks like a ten pin strip of tape and put it on the ribbon cable covering the pins around the area im targeting then using a desk lamp, magnifying glass and a sharp razor blade, i cut away at the tape to reveal pins until i have as many revealed as possible and still have good picture.

    maybe someone has some tips. this is happening to a lot of TV's and the time it takes messing with tape makes me dream of some other way to turn these lines on and off without tape.

    also i may be wrong but im pretty sure the pins i blocked eventually weren't even the clock lines after all. according to my continuity probing the 10 clock pins should have existed only at pins 2-11 at that connector.

    also what do you think is a fair price to charge when i sell this TV? its a "ghetto fix" in my mind..but its still a 75" tv with still quite a nice picture!

    the original owner paid 1200$ for it 2 years ago and his insurance paid him out 700$ to declare it toast.

    thoughts, suggestions, prayers?
    Attached Files
    Last edited by triplefour; 07-17-2023, 10:26 PM.
    Don't fear the repair...

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