Surface Pro 4 dead - Main 8.5v power rail is 2v - Have good board to compare

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  • MicroSMD Lab
    Senior Member
    • Sep 2018
    • 143
    • Trinidad and Tobago
    #21
    Re: Surface Pro 4 dead - Main 8.5v power rail is 2v - Have good board to compare

    Hi, I'm working on a Surface Pro 4, decided to post on this thread to keep all the info in one place since it does not seem to be a popular repair.
    The device is not booting, I don't get the 8.5V that mattpd spoke about. I get 15V on source and gate of Q7002. None of the mosfets are shorted. I do get +3P3VAS. No voltages present on the BQ24770. None of the coils are shorted. I did reflow the IT8528VG but no difference. The usual suspects, diodes and resistor, are good also. Any guidance would be much appreciated, thanks.

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