Determine Fuse Size?

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  • m4a2t0t
    Badcaps Veteran
    • Mar 2013
    • 279
    • USA
    #1

    Determine Fuse Size?

    Have a DV7 notebook with LED display and no backlight.



    SMD labeled JS8 below the left side of the connector. How do I determine the max amperage? I know I can remove the fuse and jump the pads to get it working but if there is another surge it will destroy the mobo and/or panel.

    The panel in the laptop is an LG LP173WD1 (TL) (E1)



    LED Power Input Voltage 7v/12v/20v MIN/TYPICAL/MAX
    LED Power Input Current NA/20mA/25mA
    LED Power Comsumption NA/5.7W/6W
    LED Power Inrush Current 1800mA

    20V fuse and 2A to cover inrush current ?

    Any help appreciated.
    Tags: None
    • reaper57
      Badcaps Veteran
      • Sep 2014
      • 216
      • Norway
      #2
      Re: Determine Fuse Size?

      Well, if you can't find a datasheet for it you can desolder the old one, solder two wires, connect them to a multimeter and check what kind of an amperage is going to the screen (you should set the brightness to max).
      Btw are you sure that the fuse is the problem? Recently I fixed a dv6 on which the backlight wasn't working and it turned out that the cable wasn't properly inserted into the panel.
      Keyboard not detected, press F1 to continue...

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA
          #3
          Re: Determine Fuse Size?

          Are you sure Js8 is for the fuse, I see JS6, JS7 close by.
          Never stop learning
          Basic LCD TV and Monitor troubleshooting guides.
          http://www.badcaps.net/forum/showthr...956#post305956

          Voltage Regulator (LDO) testing:
          http://www.badcaps.net/forum/showthr...999#post300999

          Inverter testing using old CFL:
          http://www.badcaps.net/forum/showthr...er+testing+cfl

          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
          http://s807.photobucket.com/user/budm/library/

          TV Factory reset codes listing:
          http://www.badcaps.net/forum/showthread.php?t=24809

            Comment

            • trebo
              Badcaps Veteran
              • Feb 2010
              • 514
              • Wales, UK
              #4
              Re: Determine Fuse Size?

              have you jumpered the jumper???
              those jumpers are common on boards, you should be able to find one on any scrap M/B

                Comment

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