LG 55LM6200 Backlight shuts off

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  • Kmaynard3rol
    New Member
    • Apr 2019
    • 3
    • USA
    #1

    LG 55LM6200 Backlight shuts off

    The tv works great for 20 minutes or so. Then the backlight shuts off. It seems like a thermal issue. When I turn the backlight down to 20%, I get over 35 minutes out of it. When I cycle the power, the backlight will light for only 15 seconds or so. I would guess heat soak. When the backlight is off, there is an amber status led on the power board which flashes 4 times. Does anyone know what this is? Is it the backlight strips or the backlight control circuit? Does anyone have a legend for the status led?

    Thanks,
    Ken Maynard
    Tags: None
    • diif
      Badcaps Legend
      • Feb 2014
      • 6978
      • England
      #2
      Re: LG 55LM6200 Backlight shuts off

      Sounds like LED(s) failure to me.

        Comment

        • neilc6
          Badcaps Legend
          • Nov 2015
          • 1550
          • Canada
          #3
          Re: LG 55LM6200 Backlight shuts off

          Could either be backlights (this model is edge-lit) or BGA failure on the main board.

          https://ebay.us/t1VC9L

            Comment

            • Kmaynard3rol
              New Member
              • Apr 2019
              • 3
              • USA
              #4
              Re: LG 55LM6200 Backlight shuts off

              Originally posted by neilc6
              Could either be backlights (this model is edge-lit) or BGA failure on the main board.

              https://ebay.us/t1VC9L
              What is the BGA?

                Comment

                • diif
                  Badcaps Legend
                  • Feb 2014
                  • 6978
                  • England
                  #5
                  Re: LG 55LM6200 Backlight shuts off

                  Originally posted by Kmaynard3rol
                  What is the BGA?
                  Ball Grid Array, the solder balls under the main processor.

                    Comment

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