55uf860v - Can a panel be Bad but still display perfect menus?

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  • Hamie
    Badcaps Legend
    • Apr 2014
    • 1383
    • UK
    #1

    55uf860v - Can a panel be Bad but still display perfect menus?

    Got this 4k LG.

    Shows what I would assume was a faulty mainboard.
    Multicoloured raster on all inputs including coax, sound remains, displays perfect menus.

    I have several TCONs in stock for other UF models, some compatible, some not. Some made the menus and start up image black and white. However none changed the fault. (I didn't think it was a TCON fault but worth trying)

    So I bought a replacment main board.
    And of course the fault remains.

    This does appear to be a common fault on these 4k UF sets I've seen a few others for sale with the same issue.

    However I'm not convinced I've bought a bad mainboard. Im leaning towards bad panel, purely due to the way it starts up. It displays a thin multicolor horizontal line right at the start, running right along the top. For about a second. pics to follow after this post.


    Personally never seen it before when the menus are ok but the panel is bad, so this could be a first.
    Tags: None
    • Hamie
      Badcaps Legend
      • Apr 2014
      • 1383
      • UK
      #2
      Re: 55uf860v - Can a panel be Bad but still display perfect menus?

      Pics
      Attached Files

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        • Hamie
          Badcaps Legend
          • Apr 2014
          • 1383
          • UK
          #3
          Re: 55uf860v - Can a panel be Bad but still display perfect menus?

          OK so answering my own question.

          Changed the mainboard and TCON over to a 49UF

          This one has a confirmed good panel, and the fault remains.

          This is looking like very common fault on these UF mainboards. I've seen a few now with exactly the same fault.

          Cracked solder a possibility as the heatsinks run extremely hot.

          Could have easily been solved if they part worked from eBay and saved my self questioning my sanity.

            Comment

            • dskall
              Badcaps Legend
              • Oct 2016
              • 2905
              • usa
              #4
              Re: 55uf860v - Can a panel be Bad but still display perfect menus?

              Well you could be the first to identify the exact cause.
              I assume no responsibility for any stupid suggestions I might post.

                Comment

                • EUWest
                  Member
                  • May 2019
                  • 44
                  • Germany
                  #5
                  Re: 55uf860v - Can a panel be Bad but still display perfect menus?

                  Originally posted by Hamie
                  Cracked solder a possibility as the heatsinks run extremely hot.

                  Could have easily been solved if they part worked from eBay and saved my self questioning my sanity.
                  Hi Mate! Have the Same issue. My heatsink will get very hot. Caused from the ic i think. But which solder Do you mean?

                    Comment

                    • Moreno83
                      Badcaps Legend
                      • Jun 2014
                      • 2008
                      • The Netherlands
                      #6
                      Re: 55uf860v - Can a panel be Bad but still display perfect menus?

                      Solder under the CPU(s).

                      Search for BGA solder on youtube. So you need the reflow the cpu and add better cooling.
                      I only repair Panasonic plasma tv's! Currently owning a TX-P55VT50 and still searching for a ZT60!

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