Lg smart tv 47ln5700 flashes screen then black screen

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  • mattstolte
    Badcaps Veteran
    • Dec 2013
    • 612
    • usa

    #1

    Lg smart tv 47ln5700 flashes screen then black screen

    I checked all the voltages and they are correct, screen flashes on when powers up then goes black but stays on. I even unplugged tcon and tried it and does same thing. Is this main board or panel??? Can a main board still have pwr-on and still be at fault?
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  • JeffJ
    Senior Member
    • Apr 2012
    • 189
    • Canada

    #2
    Re: Lg smart tv 47ln5700 flashes screen then black screen

    If i had to make a bet bad led strip. I thought i was the only one now two more in the last week. Measure your LED back light outputs. I bet they are 75-80v. dropping from about 115v. You have a burnt LED strip.

    Reference: https://www.badcaps.net/forum/showthread.php?t=44537
    and https://www.badcaps.net/forum/showthread.php?t=38605

    Your guts are exactly like my 47ln5750

    Comment

    • mattstolte
      Badcaps Veteran
      • Dec 2013
      • 612
      • usa

      #3
      Re: Lg smart tv 47ln5700 flashes screen then black screen

      Yes that is whats wrong thanks jeff

      Comment

      • chicago77
        Member
        • Oct 2014
        • 15
        • USA

        #4
        Re: Lg smart tv 47ln5700 flashes screen then black screen

        Originally posted by mattstolte
        Yes that is whats wrong thanks jeff
        Any idea what the part number / cost is for the LED strip?

        Comment

        • dick_barton
          Badcaps Legend
          • Aug 2015
          • 6642
          • Wales

          #5
          Re: Lg smart tv 47ln5700 flashes screen then black screen

          You would need to remove the panel to find out how many leds are faulty and if they are on the left or right hand strips. There may be 4 different strips.

          Example from Ebay
          LG 47LN5700-UH
          LEFT & RIGHT Set Backlight LED
          Strips# 6916L-1174A 6916L-1175A 6916L-1176A 6916L-1177A
          One piece of each (R1,R2,L1,L2)



          An ebay search or shopjimmy for parts.
          Last edited by dick_barton; 02-16-2017, 04:58 PM.
          Willing to help but I'm no expert.

          Comment

          • dakotadevans
            New Member
            • Dec 2017
            • 2
            • United States

            #6
            Re: Lg smart tv 47ln5700 flashes screen then black screen

            I have a 47ln5750 with a similar issue. I have 3 rows of LEDS blinking and 3 not. I switched the LEDs around and all 6 strips do work, but only in the same 3 rows. I swapped out the power board with a known good one and the same 3 rows blink. Is it a known possibility that the thin board that the LED strips plug into is bad or maybe the 4 wire cable from the power board to that board? If it is that board where can I get one, i have not seen any online. Thanks

            Comment

            • dskall
              Badcaps Legend
              • Oct 2016
              • 2905
              • usa

              #7
              Re: Lg smart tv 47ln5700 flashes screen then black screen

              You should be able to jump around your connections and fix problem
              I assume no responsibility for any stupid suggestions I might post.

              Comment

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