Before I dump this Panel...

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  • Ancient1
    Badcaps Veteran
    • Dec 2019
    • 275
    • Israel

    #1

    Before I dump this Panel...

    Hi

    I was working all day on a 42" with no backlight = Driver is bad . LED Tester. Image exists

    As I was reassembling, I discovered faults on the screen ( used the LED Tester to power the strips).

    Right distribution board, 2 Flexs, near them:
    The one near the center has 1" line on screen. Pressing on the board-side or Panel side of the Flex bonding place results in some change, I sensed heating one time, but main fault line remains
    The other, pressing on the Panel to the Chassey and the lines disappears 99.99%

    I tried taping but this didn't change anything really.

    I inspected the Flex , board side ( the Panel side is between 2 layers ) with x10 magnification and saw nothing.

    I'm about to throw it away, perhaps I'll try to fix the ( Single ) Main board

    So I decided to seek 2nd opinion What do you think ?

    * I'm thinking now that perhaps the Backlight power and the Panel stripes are connected .. The driver has stby V but fails to go High enough . PWM issue ? DIM ? - some line from the CPU area isn't correct
    Attached Files
    Last edited by Ancient1; 10-23-2022, 11:18 AM.
  • nomoresonys
    Badcaps Legend
    • Jan 2013
    • 12141
    • U.S.

    #2
    Re: Before I dump this Panel...

    if applying a little pressure on the the tab bonds makes the picture clear up, shims will probably restore the contact and give you a good picture.

    Comment

    • nomoresonys
      Badcaps Legend
      • Jan 2013
      • 12141
      • U.S.

      #3
      Re: Before I dump this Panel...

      video example there: https://www.youtube.com/watch?v=purk_SyiT44

      Comment

      • Ancient1
        Badcaps Veteran
        • Dec 2019
        • 275
        • Israel

        #4
        Re: Before I dump this Panel...

        As I write : this method , that I already know of, works on the stripe near the edge. NOT on the one in the middle - though it has some effect.
        This , and because of the priximity to the Flex, is why I figure the bonding issue isn't fixable. And it seems to be the bonding because Taping ( in groups, all tracks ) had no real effect.

        Comment

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