HP 6910p reverse polarity issue

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  • mpikou
    Senior Member
    • Jun 2013
    • 58
    • Greece

    #1

    HP 6910p reverse polarity issue

    Hi,

    i got a HP 6910p laptop. Client has put an ac adapter with reverse polarity. From then, its dead. I am searching at the board in order to find the diode with must be there in order to protect but i cant locate it.

    Can anyone help or provide a schematic for that board ?

    Thanks in adavanced.
  • atsio
    Badcaps Veteran
    • Oct 2013
    • 819
    • Greece

    #2
    Re: HP 6910p reverse polarity issue

    Try those, one is UMA the other Discrete

    https://cdn.badcaps-static.com/pdfs/...42bb0c2769.pdf
    https://cdn.badcaps-static.com/pdfs/...ac17446eca.pdf

    Comment

    • mpikou
      Senior Member
      • Jun 2013
      • 58
      • Greece

      #3
      Re: HP 6910p reverse polarity issue

      Hi,

      Thank you VERY much for the schematics and the reply.

      I cant locade the diodes to the board... could you please help me ?

      Here are photos of the board.
      http://imageshack.com/a/img901/6906/BlJKfe.jpg
      http://imageshack.com/a/img540/3535/xOq3Jx.jpg
      http://imageshack.com/a/img538/9500/jFcn3e.jpg
      http://imageshack.com/a/img913/7939/KgJ51M.jpg

      Thanks

      Comment

      • dj_ricoh
        Badcaps Legend
        • Jan 2013
        • 2073
        • uk

        #4
        Re: HP 6910p reverse polarity issue

        Did you saw,smell or hear something?

        If not discharge the board and give it one more try.
        Just cook it! It's already broken.

        Comment

        • mpikou
          Senior Member
          • Jun 2013
          • 58
          • Greece

          #5
          Re: HP 6910p reverse polarity issue

          Originally posted by dj_ricoh
          Did you saw,smell or hear something?

          If not discharge the board and give it one more try.
          Nothing smells, no sound at all and not something burn/wrong with optican observation.

          Fully disharged and issue persists.

          Comment

          • atsio
            Badcaps Veteran
            • Oct 2013
            • 819
            • Greece

            #6
            Re: HP 6910p reverse polarity issue

            What's the current drawn when you plug in lab supply?

            Comment

            • mpikou
              Senior Member
              • Jun 2013
              • 58
              • Greece

              #7
              Re: HP 6910p reverse polarity issue

              If i have undertand correct what you are asking, its 19V.

              Comment

              • R_J
                Badcaps Legend
                • Jun 2012
                • 9535
                • Canada

                #8
                Re: HP 6910p reverse polarity issue

                On page 37 of the first diagram, PCN1 is the input jack, the adaptor voltage should go through coil PL1 and be on (VIN) on the next page (38) VIN comes to fet PQ3 & PQ5 etc. I would check parts in that area. Is there voltage on P2 or P4 or B+

                Comment

                • ktmmotocross
                  Boardkiller
                  • Feb 2014
                  • 3577
                  • slovakia

                  #9
                  Re: HP 6910p reverse polarity issue

                  post photo of area around power connector. both side.

                  Comment

                  • atsio
                    Badcaps Veteran
                    • Oct 2013
                    • 819
                    • Greece

                    #10
                    Re: HP 6910p reverse polarity issue

                    Originally posted by mpikou
                    If i have undertand correct what you are asking, its 19V.
                    Όχι τα αμπέρ που τραβάει από το τροφοδοτικό σου, όταν το κουμπώνεις (χωρίς να ξεκινήσεις το laptop).

                    Comment

                    • mpikou
                      Senior Member
                      • Jun 2013
                      • 58
                      • Greece

                      #11
                      Re: HP 6910p reverse polarity issue

                      Originally posted by R_J
                      On page 37 of the first diagram, PCN1 is the input jack, the adaptor voltage should go through coil PL1 and be on (VIN) on the next page (38) VIN comes to fet PQ3 & PQ5 etc. I would check parts in that area. Is there voltage on P2 or P4 or B+
                      PL1 its ok, PQ5 ok, but i cant locate PQ3.


                      Originally posted by ktmmotocross
                      post photo of area around power connector. both side.
                      Here are the photos.
                      http://imageshack.com/a/img537/4334/jiMNoL.jpg
                      http://imageshack.com/a/img910/5082/Oe3G2k.jpg

                      Originally posted by atsio
                      Όχι τα αμπέρ που τραβάει από το τροφοδοτικό σου, όταν το κουμπώνεις (χωρίς να ξεκινήσεις το laptop).
                      Ευχαριστώ για την διευκρίνηση.

                      Comment

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