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.
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    • 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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