Lenovo Y50-70 (LA-B11P) no charge problem

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  • agswireless
    Member
    • Jul 2022
    • 15
    • USA

    #1

    Lenovo Y50-70 (LA-B11P) no charge problem

    ok so I have this Lenovo y50-70 touch that has a no charge problem, maybe someone can point me in the right Direction since I cannot find a schematic for Borderview
    what are you guys opinion on where to start to check why its not charging?

    Back story:
    I bought this with a bad charging port, previous owner stated it charge fine but his kid kicked the cord and rip the plug and port out.
    so I ordered a new one, but when I was replacing the plug the open wire touch and made a spark because I completely forgot to unplug the battery.
    so I went a head changed out the plug and put it back together and it doesn't charge, no light or nothing i know that laptop works had a full charge before the battery drained.

    thing I done so far:
    replaced the port.
    replaced one of the mosfets because I had an extra one laying around, but no luck
    I tested the volt on the plug side of the board it gets 19V
    I measured the first mosfet PQ301 the drain and gate both sides measure 19v
    mosfet PQ302 gate measure 19v in and drain out 5v both the old mosfet and new one measure the same
  • mon2
    Badcaps Legend
    • Dec 2019
    • 14191
    • Canada

    #2
    Post the topside markings of each mosfet.

    Remove all power. Meter in resistance mode. Measure the resistance across the mosfet.

    source & drain
    source & gate
    gate & drain


    Repeat for next mosfet.

    Comment

    • agswireless
      Member
      • Jul 2022
      • 15
      • USA

      #3
      resistance mode (200k) selected crappy multimeter
      I have to buy a better one

      1. mosfet 4447A
      S&D= 0 Continuity (beep)
      S&G= 0
      G&D= 0
      its short to ground I tested it in continuity, its the same results with the new and old mosfet

      2. mosfet S3604
      S&D= 103
      S&G= 0
      G&D= 107

      read high then numbers start to drop

      Comment

      • mon2
        Badcaps Legend
        • Dec 2019
        • 14191
        • Canada

        #4
        Remove both mosfets and then check the resistance across the pcb pads again. No power in resistance checks. Then check the resistance to ground for each mosfet; each pin group ( source / gate / drain). Flux the area well; remove with patience so pcb pads are not lifted.

        post clear pics of this portion of the logic board.

        Comment

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