Hp FN747AA

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  • Fisher77
    Badcaps Veteran
    • Feb 2016
    • 229
    • USA

    #1

    Hp FN747AA

    My monitor died. There was a funky sound from the speakers and the monitor did alot of jumping around(interference jitter is the best way to explain it), and then went black. When I turn it on now all it does is faintly flash on and off. I tried it on a different PC with the same results. I removed all the covers and reconnected it to a computer and I can hear a pulsating buzzing noise coming from the power supply. The power on led pulsates along with the noise. All voltages on CN902 are good except there is no voltage on DIM.

    Any help is greatly appreciated.
    Attached Files
  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: Hp FN747AA

    So the backlight comes up for a second? Did you follow the troubleshooting steps here: https://www.badcaps.net/forum/showthread.php?t=10419 ?
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

    Comment

    • Fisher77
      Badcaps Veteran
      • Feb 2016
      • 229
      • USA

      #3
      Re: Hp FN747AA

      Originally posted by piernov
      So the backlight comes up for a second?

      It flashes on and off very dimly. Can barely see it.

      Comment

      • Fisher77
        Badcaps Veteran
        • Feb 2016
        • 229
        • USA

        #4
        Re: Hp FN747AA

        Originally posted by Fisher77
        It flashes on and off very dimly. Can barely see it.
        Better way to describe it is the backlight flash on and off repeatedly. The screen never goes to just black.

        Comment

        • 1supertech
          Badcaps Veteran
          • Apr 2012
          • 384
          • USA

          #5
          Re: Hp FN747AA

          Change all capacitors if you don't have an ESR meter

          Comment

          • Fisher77
            Badcaps Veteran
            • Feb 2016
            • 229
            • USA

            #6
            Re: Hp FN747AA

            Originally posted by 1supertech
            Change all capacitors if you don't have an ESR meter
            That did the trick. I appreciate it 1supertech. I have never seen a failed cap that wasnt bulging. Time to get or build an ESR meter.

            Comment

            • 1supertech
              Badcaps Veteran
              • Apr 2012
              • 384
              • USA

              #7
              Re: Hp FN747AA

              Great!!

              Comment

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