A2991 logic board issue, 20volts 0 amps help!

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  • Stephen
    Meow Meow MEOW!
    • Apr 2020
    • 672
    • United States

    #1

    A2991 logic board issue, 20volts 0 amps help!

    Customer plugged in samsung monitor into the board and used it as a power supply, killed UG800 and UG400. I replaced those two with an exact donor board we had In stock and working, board pulls 5volts and then gets like 2.89 amps on the left side. The singular port is the port that failed. Used a perfectly working chips from donor (board was locked) Now I only get 5volts 0 amps on that power and then 20volts 0 amps on the two left side ports, I checked for DFU and nope nothing, computer not turning on. No shorts present anymore. I am confused as I used the exact components from an identical working board. So I am now stuck tracing the issue. I am only getting 12volts at PPBUS_AON . PP3v3 is present and P1v8 is present but nothing. I also put it into the battery and nothing. So I'm lost now. Very confused where I am missing as there are no present shorts here. Am I missing something?
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