HP DV7 Component Ident.

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  • Kilroy2k1
    Senior Member
    • Aug 2009
    • 69

    #1

    HP DV7 Component Ident.

    I have a DV7-1428ca laptop that the my daughter spilled something on and a drip got on the motherboard in a couple areas. The worst so far is a corroded resistor, bad enough i cant get a value reading.
    If anyone would happen to have a dv7 1400 or 1200 series motherboard would it be possible to measure the value of a resistor for me?
    The item in question is in the circle on the image and is labled R871 on the board.
    Thanks for any assistance.
    Tom.


  • ablacon64
    Senior Member
    • Jan 2011
    • 89

    #2
    Re: HP DV7 Component Ident.

    It may be difficult for someone to have the same motherboard to measure the component. It's better if you post the MB model, maybe someone may take a look at the schematics. The MB model is something like LA-xxxxP, usually next to the memory slots or keyboard connector.

    Comment

    • Kilroy2k1
      Senior Member
      • Aug 2009
      • 69

      #3
      Re: HP DV7 Component Ident.

      Thanks for the reply, There are a ton of numbers on here so I'm glad you clued me in on which one is necessary.
      The number on this one is JBK00 LA-4091P
      I Hope someone has the schematics or a matching board to measure up

      Thanks again
      Tom.

      Comment

      • yyonline
        Badcaps Veteran
        • Jul 2009
        • 692
        • USA

        #4
        Re: HP DV7 Component Ident.

        From the datasheet:
        R871
        330K_0402_5%

        So 330Kohm resistance, 5% tolerance, 0402 size.

        Comment

        • Kilroy2k1
          Senior Member
          • Aug 2009
          • 69

          #5
          Re: HP DV7 Component Ident.

          Thank you very much sir.
          I'll get that replaced in the morning and see if it solves the issue this unit has developed.
          Thanks again
          Tom.

          Comment

          • Kilroy2k1
            Senior Member
            • Aug 2009
            • 69

            #6
            Re: HP DV7 Component Ident.

            Apparently that is not the only problem on the board. I replaced the resistor and the unit still shuts down 3 seconds after headphones are plugged in and the IR remote reciever does not work.
            Would anyone have any ideas where to look?
            Or maybe i whould start a new topic..

            yyonline would there be any possibility of getting a copy of the schematic or just the parts pertaining to this section?

            Thanks
            Tom.

            Comment

            • ablacon64
              Senior Member
              • Jan 2011
              • 89

              #7
              Re: HP DV7 Component Ident.

              Does the unit work fine without plugging the headphones?

              Comment

              • Kilroy2k1
                Senior Member
                • Aug 2009
                • 69

                #8
                Re: HP DV7 Component Ident.

                Yes everything else but the IR reciever for the remote and the headphone outout works well.
                The IR does show a voltage change when you point and shoot the remote, but there may be a problem in the chip that translates it.

                Audio works fine from the laptops speakers.

                I isolated the jack daughterboard and manually pulled the sense line (3.4V) to ground and it still shuts the unit down after 3 seconds.
                It seems like the sense line runs through 2 6 pin transistors, Q20 and Q148, between the codec chip and the jack daughter board so I am wondering if something in that little mess is shorting and tripping the protect.
                I've been trying to identify those two transistors but the markings of MNIVO dont come up at all.

                Comment

                • Kilroy2k1
                  Senior Member
                  • Aug 2009
                  • 69

                  #9
                  Re: HP DV7 Component Ident.

                  Well audio is fixed. found some more corrosion over by the docking port, cleaned it up and touched up a few solder joints.
                  The IR is still out to lunch tho..

                  Comment

                  • ablacon64
                    Senior Member
                    • Jan 2011
                    • 89

                    #10
                    Re: HP DV7 Component Ident.

                    Have you checked bios config for IR?

                    Comment

                    • Kilroy2k1
                      Senior Member
                      • Aug 2009
                      • 69

                      #11
                      Re: HP DV7 Component Ident.

                      I took a quick look in there and didnt see anything relating to the IR.

                      With some probing I see the IR functioning but only getting a .09V fluctuation when hitting a button on the remote, this seems a little low to me.

                      Comment

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