Samsung Samtron 74V backlight is always on.

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  • tama4tama
    Senior Member
    • Nov 2006
    • 56

    #1

    Samsung Samtron 74V backlight is always on.

    Dear Brothers,

    This is another monitor Samsung Samtron 74V it came in with two capacitors bad, the capacitors has been replaced but the problem now is that the backlight is always on when I power off from the panel, unless I put it off from the mains before the screen goes off.

    Tama
  • PlainBill
    Badcaps Legend
    • Feb 2009
    • 7034
    • USA

    #2
    Re: Samsung Samtron 74V backlight is always on.

    Originally posted by tama4tama
    Dear Brothers,

    This is another monitor Samsung Samtron 74V it came in with two capacitors bad, the capacitors has been replaced but the problem now is that the backlight is always on when I power off from the panel, unless I put it off from the mains before the screen goes off.

    Tama
    Check your work. It is most likely a bit of solder shorted to another path when you replaced the capacitors.

    PlainBill
    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

    Comment

    • tama4tama
      Senior Member
      • Nov 2006
      • 56

      #3
      Re: Samsung Samtron 74V backlight is always on.

      This morning, when put on the monitor it flash with back lights on and went off.

      I have checked the solder which I did but all look good.

      Comment

      • jayoung
        Senior Member
        • May 2011
        • 172

        #4
        Re: Samsung Samtron 74V backlight is always on.

        Sounds like possibly "2 Seconds to Black"

        https://www.badcaps.net/forum/showthread.php?t=10419

        Most on the forums here recommend replacing all of the capacitors on the power supply board (with exception of the large capacitor). If two of them were showing signs of failure, some of the others may be failed and not showing it, or on their way to failing.

        Comment

        • tama4tama
          Senior Member
          • Nov 2006
          • 56

          #5
          Re: Samsung Samtron 74V backlight is always on.

          Thanks for your help; I will try to replaces all the capacitors as you said and let you know the out come of.

          Tama
          Attached Files

          Comment

          • jayoung
            Senior Member
            • May 2011
            • 172

            #6
            Re: Samsung Samtron 74V backlight is always on.

            Bad capacitors is just one of several causes of "2 Seconds to Black." Others include bad ccfl's and / or wiring to them, bad transformers, etc. They are listed in detail in the link from my last post. Make sure you are replacing the capacitors with good quality low ESR capacitors, anything else will either not work or fail quickly. A list of good quality low ESR capacitors can be found in the following link:

            https://www.badcaps.net/forum/showthread.php?t=2280

            Comment

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