LG 47LN5400 TV Backlight problem

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  • SurrealMustard
    Badcaps Veteran
    • Jan 2015
    • 486
    • The United States of America

    #41
    Update

    The two L2 Led strips arrived and I installed them right away. I also used the remaining good Leds from the strips that were replaced to replace the bad ones on the other strips throughout the set and now everything is working 100%!
    Attached Files

    Comment

    • CapLeaker
      Leaking Member
      • Dec 2014
      • 8146
      • Canada

      #42
      Re: LG 47LN5400 TV Backlight problem

      Perfect!

      Comment

      • Thorn
        New Member
        • Nov 2016
        • 2
        • Us

        #43
        Re: LG 47LN5400 TV Backlight problem

        Same issue here. Sound still see picture but no back light. traced it back to bad LEDs, replaced all. Problem still persisted, replaced power supply just in case it had some unseen issue(I believe the inverter is part of it) no change.. Tore it back down to LEDs, turns out one led bad on one strand...these were brand new! :/ got a replacement for that strand, tested all LEDs again,all test good now, but problem persists!
        One thing that is happens when you turn it on now and you get the notorious "flash, then nothing" 3 led strands are not flashing up even though they test good with direct power Scratching my head. I tested all LEDs, output voltage on PSu, and tested on the leads on the ribbon cable from the main board, all voltage seem right except the bottom lead on ribbon(blue cable ) tested 3.27v where it is printed 3.5v specs? Is there some small issue on the main board?

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #44
          Re: LG 47LN5400 TV Backlight problem

          What are the spec of the replacement LED?
          Never stop learning
          Basic LCD TV and Monitor troubleshooting guides.
          http://www.badcaps.net/forum/showthr...956#post305956

          Voltage Regulator (LDO) testing:
          http://www.badcaps.net/forum/showthr...999#post300999

          Inverter testing using old CFL:
          http://www.badcaps.net/forum/showthr...er+testing+cfl

          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
          http://s807.photobucket.com/user/budm/library/

          TV Factory reset codes listing:
          http://www.badcaps.net/forum/showthread.php?t=24809

          Comment

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