Buffer board or ysus?

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  • Cosmo66
    Senior Member
    • Nov 2012
    • 87
    • USA
    #1

    Buffer board or ysus?

    Hello everyone,

    This is my first post here, I'm fairly new to TV repair as well.

    I have a 42 inch HP plasma TV with the usual sound but no picture issue. After replacing the Ysus board, the TV came right back to life.

    Unfortunately, there was a single thin horizontal black line along the bottom the lower half of the screen. Thinking it was most likely a loose ribbon cable, I opened and closed the ribbon cable a few times, (here comes the dumb part) with the power on.

    I know, I know, I know, stupid.

    Anyways, while doing this, I fried something and now the picture has vertical lines running top to bottom and colored squares everywhere. They are not in one place, they are scrambled and move around. For example, a color that should appear in the image on screen appears as an entire vertical line top to bottom during those frames.

    I have not ever seen this symptom, but I suspect I just killed the new ysus that I installed? Either that or the buffer board. I see nothing obvious upon visual inspection and all fuses are intact.

    Thank you in advance for any help

    **The pictures show what would normally be the menu screen with the hp logo floating around. The thick vertical line moves around in the same manner***
    Attached Files
    Last edited by Cosmo66; 11-04-2012, 10:51 PM.
    Tags: None
    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK
      #2
      Re: Buffer board or ysus?

      It looks like the plasma panel itself is damaged (the horizontal drivers are damaged.) It is unrepairable as they are bonded to the plastic flex which is bonded to the glass. However if that bar moves then it is likely to be Y-buffers.
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

        Comment

        • rayrod81
          Badcaps Veteran
          • Oct 2010
          • 205
          #3
          Re: Buffer board or ysus?

          Yes it looks like the normal fault when the buffers go bad on the LG chassis. This happens quite a bit on the 50" plasmas. You most likely shorted the buffer when you were trying to adjust the ribbon cable.

            Comment

            • Cosmo66
              Senior Member
              • Nov 2012
              • 87
              • USA
              #4
              Re: Buffer board or ysus?

              Thanks for the help. I'm going to order the buffer boards and I'll update the thread with my results. I suspected the buffer boards, but I thought maybe the Y sustain could cause these same symptoms.

              I really hate to put anymore money into this TV, but I also hate to scrap it.

                Comment

                • Cosmo66
                  Senior Member
                  • Nov 2012
                  • 87
                  • USA
                  #5
                  Re: Buffer board or ysus?

                  Replaced the Y-buffer. TV is good as new. The horizontal black line disappeared too.

                  Thanks for the help guys, I really appreciate it!

                    Comment

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