LG 29LB4510 - Backlight on no display

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  • caphair
    Badcaps Legend
    • Nov 2011
    • 1249
    #1

    LG 29LB4510 - Backlight on no display

    Powers on/off fine. Backlight visible but nothing on the screen, just black display.

    Made following checks on t-con

    V33v12 = 3.3v
    Vgl = -7.8v
    Vgh = 27v
    Rx5 = 3.3v
    Rx4 = 3.3v
    Rx3 (1k ohm) = 0v
    Rx2 = 3.3v
    Rx1 = 3.3v

    Not sure what else to check for at this point
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    • caphair
      Badcaps Legend
      • Nov 2011
      • 1249
      #2
      Re: LG 29LB4510 - Backlight on no display

      Anyone?

        Comment

        • R_J
          Badcaps Legend
          • Jun 2012
          • 9535
          • Canada
          #3
          Re: LG 29LB4510 - Backlight on no display

          This is when a scope is useful, without it you are guessing, is it the main board not outputting a video signal? or is it that t-con not processing the signal?

            Comment

            • caphair
              Badcaps Legend
              • Nov 2011
              • 1249
              #4
              Re: LG 29LB4510 - Backlight on no display

              Unfortunately don’t have a scope. Maybe I could borrow one. Where would I be probing with it?

                Comment

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