LG 43SM5KB Backlight working but no image

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  • Pxxx3104
    New Member
    • Jun 2025
    • 8
    • Philippines

    #1

    LG 43SM5KB Backlight working but no image

    Good day! Does anyone here familiar with the TCon from LG: 6870c-0532b. The problem is that the TV displays no image but backlight and audio from TV is good. I have checked the 125V/2A fuse and it reads 160~180 ohms. Could it be that the only problem is the fuse? Any suggestions and recommendation is highly appreciated.

    Note that it is only my first time to try and troubleshoot TVs.

    Thank you and have a nice day!
  • Davi.p
    Hobbist Tech
    • Sep 2009
    • 4465
    • Italy - Milan

    #2
    Get deeper on the fuse pressing probes and twisting, retest the fuse..

    Comment

    • lotas
      Badcaps Legend
      • Jan 2016
      • 4753
      • Russia

      #3

      So check the voltage relative to ground at the input of this fuse and at its output.

      Comment

      • Pxxx3104
        New Member
        • Jun 2025
        • 8
        • Philippines

        #4
        I am currently away from the TV now. I will get back to this thread when I get my hands back on the TV. Thank you for the answers guys!

        Comment

        • Pxxx3104
          New Member
          • Jun 2025
          • 8
          • Philippines

          #5
          Hi! It took longer than I expected to get back to the TV. I checked the input relative to ground and it is ~13.20V but on the output side it only reads ~11.19. I already tried to replace the LVDS ribbon but still no luck.

          Comment

          • Davi.p
            Hobbist Tech
            • Sep 2009
            • 4465
            • Italy - Milan

            #6
            replace the fuse..

            Comment

            • Pxxx3104
              New Member
              • Jun 2025
              • 8
              • Philippines

              #7
              So I went in and replace the fuse. But sadly it's still not working. Any checkpoints I can check to verify if the issue is within the Tcon or from somewhere else?

              Comment

              • Davi.p
                Hobbist Tech
                • Sep 2009
                • 4465
                • Italy - Milan

                #8
                Retest the fuse, it's so strange a drop of 2v on it.. you probably have a short on the tcon..

                Comment

                • Pxxx3104
                  New Member
                  • Jun 2025
                  • 8
                  • Philippines

                  #9
                  i will just replace the tcon. i'll get back if I already receive and replaced the tcon. thank you for your replies

                  Comment

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