75UK6190 blank screen, shorted caps on panel strips

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  • mecha1166
    Member
    • Apr 2011
    • 37

    #1

    75UK6190 blank screen, shorted caps on panel strips

    I have 2: 75UK6190 units. One has a broken panel - it lights up and shows a bit of graphics. The other LG tv lights up but has no video. Turns on/off ok, and I swapped all the boards to check them all. I exposed the strips on the bottom of both panels. I tested the caps along the LED strips on the bottom of the panel. About 12 smd cap chips on the tv with no video, test shorted. I talked to LG tech support but they do not repair to this level, they just replace the panel. Now, there is a Philips mainboard that a smd capacitor chip shorts and causes a squeal from the power supply, and the fix is to simply remove it. Has anyone had experience replacing the smd capacitors on LED panel control strips or repairing them?
  • mecha1166
    Member
    • Apr 2011
    • 37

    #2
    Re: 75UK6190 blank screen, shorted caps on panel strips

    Here is some LED panel strip repair information:
    https://www.vislcd.com/full-repair-g...creen-failure/

    Comment

    • mecha1166
      Member
      • Apr 2011
      • 37

      #3
      Re: 75UK6190 blank screen, shorted caps on panel strips

      I would not apply voltage to see what might be shorted like this, but shorted caps are talked about here: https://www.youtube.com/watch?v=YsZiUzqIZeE

      Comment

      • dskall
        Badcaps Legend
        • Oct 2016
        • 2905
        • usa

        #4
        Re: 75UK6190 blank screen, shorted caps on panel strips

        If you have shorted caps doesn't mean they're all shorted. Or even that it is a cap that is shorted. Voltage injection is probably the easy way to find short.
        I assume no responsibility for any stupid suggestions I might post.

        Comment

        • mecha1166
          Member
          • Apr 2011
          • 37

          #5
          Re: 75UK6190 blank screen, shorted caps on panel strips

          Thanks for your reply & help. I have a good (but cracked) panel and the one with possible shorts. I'll sit down and start pulling components and comparing readings, to locate the short. I have replaced chips on t-cons before. I'd hate to throw away an uncracked panel, or sell it for $50 to the Mexican buyers that come through each month.
          Thanks,
          jim

          Comment

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