Trouble finding short on 3V rail

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  • p1muserfan
    Senior Member
    • Apr 2014
    • 184
    • USA

    #1

    Trouble finding short on 3V rail

    I'm having a hard time finding the short on the 3v rail of this board. Pin 7 of PU1 with PL4 removed (p. 32) is measuring short, so that would be +3VPCU. With my power supply set to 3v and 2a I measured 0v and 2a when I put the probe on the PL4 pad. PC35 got hot really quick, removed it. Now measuring 3v and 1.5a so is there still a short? I also made a list of things on the 3v rail and its pretty big, so is there something that usually is the problem? Nothing else seems to be getting hot. KBC is already removed. Any suggestions where to zero in on would be great
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  • fddizon
    Badcaps Veteran
    • Sep 2011
    • 555
    • Philippines

    #2
    Re: Trouble finding short on 3V rail

    Measure PL4 to ground with no power on the board.

    if low resistance, then still have a short. if you can meaure 3v then no short anymore on that rail

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