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
    Attached Files
  • caphair
    Badcaps Legend
    • Nov 2011
    • 1249

    #2
    Re: LG 29LB4510 - Backlight on no display

    Anyone?

    Comment

    • R_J
      Badcaps Legend
      • Jun 2012
      • 9518
      • 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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