Am working on hp 840 g3

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  • sullysys
    New Member
    • Aug 2014
    • 5
    • Nigeria
    #1

    Am working on hp 840 g3

    Am working on hp 840 g3.it powers once I plug the adapter ,after that it will not power.
    I notice am have 1.4v in the power button instead of 2.4..please any idea on how to fix it
    No schematic..
    Tags: None
    • reformatt
      Badcaps Legend
      • Feb 2020
      • 1403
      • Australia
      #2
      Re: Am working on hp 840 g3

      I've had some dealings with these boards. Unless its a shorted cap, they aren't the easiest to work on especially since there is no publicly available schematic. There are two coils near the SPI EEPROMS that should measure +3.3V and +5V so you can start there. Check LDO outputs of the converters for shorted caps etc. Thermal camera helps.

      I sometimes just buy a 2nd hand unit (cheap) and steal the board out of that if it's anything more complicated.

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