Acer N20C1 LA-J871P Missing +VCC_CORE and +VCC_GT

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  • Comp_Pro
    Member
    • Jun 2020
    • 33
    • USA
    #1

    Acer N20C1 LA-J871P Missing +VCC_CORE and +VCC_GT

    Hello all,

    I have this Acer motherboard LA-J871P the issue with this board is that it turns on but does not show any video or post. I measured the voltages of all the coils and all voltages are present except for +VCC_CORE and +VCC_GT. Schematic and board view can be found here at the bottom of the post. This has a dedicated graphics chip on it and that is getting voltage as well.

    I checked the driver IC PUZ2, PUZ3, PUZ4, PUZ5 and all have 5V on the ENABLE pin 3. However still no output from +VCC_CORE and +VCC_GT.

    Any ideas what the issue might be? Thank you.
    Attached Files
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    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      Re: Acer N20C1 LA-J871P Missing +VCC_CORE and +VCC_GT

      Power Plane is given on page3 of schematic. Check which rail is missing.

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