55LD520C Bad Main Board?

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  • culcuhain
    Senior Member
    • May 2016
    • 186
    • U$@
    #1

    55LD520C Bad Main Board?

    A friend brought over his LG 55LD520C LCD tv.
    Symptoms: Has red standby. Power button turns light from red to blue. No audio (from what we can tell) and no backlights.
    No bulging caps.

    P201 Connecter
    Left Side
    Marked @Standby @On
    P Dim #2 0v 0v
    12v 0v 11.6v
    12v 0v 11.6v
    12v 0v 11.6v
    GND 0v 0v
    GND 0v 0v
    3.5v 3.5v 3.5v
    3.5v 3.4v 3.5v
    GND 0v 0v
    GND 0v 0v
    24v 0v 0v
    PWR 0v 3.3v

    Right Side
    Marked @Standby @On
    Err 0v 0.9v
    P Dim#1 0v 1.7v
    A Dim 0v 3.2
    Inv_On 0v 0.0v
    GND 0v 0v
    GND 0v 0v
    3.5v 3.5v 3.5v
    3.5v 3.5v 3.5v
    GND 0v 0v
    GND 0v 0v
    24v 0v 24.2v
    24v 0v 24.2v

    To me it looks like the main board since I am not getting the BL_ON Signal (Inv_Ctl) and the Err voltage.

    I have attached a few pics. One of the pics is for the IC that controls the INV_On and it looks like some bad soldering. Y'alls thoughts?
    Also, if it is the main board, I can't seem to find the same number. Mine is EBU61044602 and I can find only EBU61044603. Will that one work?
    Attached Files
    Tags: None
    • CapLeaker
      Leaking Member
      • Dec 2014
      • 8146
      • Canada
      #2
      Re: 55LD520C Bad Main Board?

      I think you pin pointed it pretty good. Worth a shot.

        Comment

        • ReeceyBurger123
          Never Give Up !
          • May 2014
          • 7325
          • Britain
          #3
          Re: 55LD520C Bad Main Board?

          Replace the Mb and let us know how it goes
          Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

          https://www.facebook.com/Telford-Tel...7894576335359/

            Comment

            • culcuhain
              Senior Member
              • May 2016
              • 186
              • U$@
              #4
              Re: 55LD520C Bad Main Board?

              New board came in (different part# but guaranteed to work/fit) and plugged it in. T-CON connectors different so I couldn't hook that up. I left them unplugged. Plugged her in... Turned her on... Saw the blue light... heard audio (first time for me to hear audio) and backlights came on. So my main is dead and I will return this one. I need a replacement for
              EBU61044602 or a substitute part # that will work... any help?

                Comment

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