LG 60PM6700 Loud pop and now TV won't stay on

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  • Stoodo
    New Member
    • Apr 2017
    • 5
    • United States
    #1

    LG 60PM6700 Loud pop and now TV won't stay on

    LG 60PM6700 Loud pop and now TV won't stay on.

    When attempting to power on, tv will come off standby for 2 seconds then shut off again. TV will stay on if YSUS board is disconnected. (EAX64279701)

    Power board is EAY62609801.

    Should I assume YSUS board is defective?
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    • Unspun01
      Badcaps Veteran
      • Jun 2011
      • 349
      • Canada
      #2
      Re: LG 60PM6700 Loud pop and now TV won't stay on

      You are on the right track.

      If TV stays on when YSUS board is disconnected, the problem could be the YSUS or one of the Y-buffer boards connected to the YSUS.

      With all boards connected (including YSUS), try disconnecting the upper and lower buffer boards and turning on the TV. If the problem still remains after disconnecting both buffer boards, then the problem is certainly the YSUS.

      If the TV turns on and stays on with YSUS connected but upper and lower buffer boards disconnected, then the issue could be one of the Y buffer boards. You may then have to try with one buffer or the other connected to isolate which Y driver may be the issue.

      This may be one of the LG models that needs both working buffers connected to show an image. If one is not working, you will not get image.

      Without full circuit path, screen may only illuminate as dark grey for the half of the screen that is connected to a working buffer. Other half will remain completely dead.

      You can determine which buffer is the bad one by seeing if the upper or lower half of the screen dimly illuminates when only one buffer is connected when power is applied. (The connected buffer that allows screen to dimly illuminate is likely ok).
      Last edited by Unspun01; 12-19-2019, 10:59 AM.

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