LG 50PA4500 Works for 2 Minutes and Goes Into Standby

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  • Heraldj07
    New Member
    • Apr 2016
    • 4
    • United States

    #1

    LG 50PA4500 Works for 2 Minutes and Goes Into Standby

    New to this forum but loving all of the information so far.

    I currently am working on a TV for a friend who claims it was struck by lightning or power surge.

    It was connected to a COAX cable box.

    I have examined all of the boards behind the panel and see no signs of blown caps or ICs.

    Here are the symptoms.

    3 year old TV
    worked great until this last week.

    When i plug the TV in, i get 1 Click. (power relay) and everything works. Great picture and sound. If i leave it on for more than 2 minutes the screen will turn off. No Sound No Picture. The remote and buttons do nothing in this state. In order to see any picture again, i have to unplug the set and let it stand for 5 minuets and it will repeat the same issue. a few minutes on and then it goes into what i can describe as standby. After reading through this forum, i did turn out all of the lights and you can clearly see a faint image glow from the screen, When you unplug it you can see the screen turn truly black.

    To give you some of my background, i spent the better part of 5 years as a component level service repair technician. However i dont have the equipment that used to have and would rather just swap a board..... unless its a few through hole caps that are suspect. Im limited to a cheap Weller iron and some solder wick.

    I played around with unplugging the Xsus and the Ysus but i am not sure what to do from here.

    Any info would be awesome
  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6643
    • Wales

    #2
    Re: LG 50PA4500 Works for 2 Minutes and Goes Into Standby

    If you could post some clear pictures of the boards is always a good starting point for others to offer help.
    Willing to help but I'm no expert.

    Comment

    • Heraldj07
      New Member
      • Apr 2016
      • 4
      • United States

      #3
      Re: LG 50PA4500 Works for 2 Minutes and Goes Into Standby

      Here is a video of the fault.
      Pictures to come

      https://youtu.be/54zD_DIo--4

      Comment

      • Electronic Handyman
        Senior Member
        • Apr 2016
        • 58
        • Canada

        #4
        Re: LG 50PA4500 Works for 2 Minutes and Goes Into Standby

        Try disconnecting and pulling out one of the two y-sustain buffer boards and then plug the set back in and turn it on.Then try reinstalling it and pulling the other buffer board and see how the set acts.If you get half a picture on the set with only one buffer board connected and it stays running you know the buffer board you pulled is bad.

        Comment

        • Heraldj07
          New Member
          • Apr 2016
          • 4
          • United States

          #5
          Re: LG 50PA4500 Works for 2 Minutes and Goes Into Standby

          Pictures are posted on drop box https://www.dropbox.com/sh/gfccyi1t0...X7EDwJSja?dl=0

          Comment

          • Electronic Handyman
            Senior Member
            • Apr 2016
            • 58
            • Canada

            #6
            Re: LG 50PA4500 Works for 2 Minutes and Goes Into Standby

            I highly suspect that it's a power supply issue probably a regulator.

            Comment

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