50pk540

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  • tvtimmy
    Badcaps Legend
    • Mar 2015
    • 1160
    • usa

    #1

    50pk540

    I repaired a LG 50" plasma 50pk540 with an intermittent shutdown. Turned out to be cracked solder joint on a transformer on the power supply. I touched up all the major solder joints on the x and y mains while I had it apart. I pluged it in and it fires right up and never shut down( ran for 9hrs). I put the stand on it and pressed the menu button and saw 2 one pixle wide lines about 1" apart, just left of the center of the set. I tried to clean and reset the ribbon on the control board and the one that goes to the screen from the XC center buffer. No luck. I then disconnected. That ribbon again and turned it on and of course that segmet was off, but looked like a maldischarge, and I could still see faint lines. Maybe it is screen burn in, in reverse???? Gonna try a 10 dollar XC buffer. Oh, the lines dont show up on full white screen and they show on most of the test patterens. I will keep you posted.........
  • tvtimmy
    Badcaps Legend
    • Mar 2015
    • 1160
    • usa

    #2
    Re: 50pk540

    Bad panel.

    Comment

    • tw2005
      Badcaps Legend
      • Oct 2011
      • 6458
      • Australia

      #3
      Re: 50pk540

      Originally posted by tvtimmy
      Bad panel.
      yeah, had that experience twice now my self including that was perfect and was selling and whenever I get an enquiry I always like to fire it up and confirm it's good.

      Blow me, a line appeared , all that hard work .

      Comment

      • tvtimmy
        Badcaps Legend
        • Mar 2015
        • 1160
        • usa

        #4
        Re: 50pk540

        Today I got a 50Pk750 with a bad mainboard for free. It has the same panel as the 50pk540 I have with the bad panel. I swapped the mainboard, ldvs cable(to short), and the ir cable. The tv works just fine. Only thing left to do is clamp both tv backs together and drill new screw holes, as only 4 match up now.

        Comment

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