A1708 820-00840 MacBookPro No-Brains weird CPU voltage.

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  • abajor
    Senior Member
    • Feb 2024
    • 175
    • United States
    #1

    A1708 820-00840 MacBookPro No-Brains weird CPU voltage.

    I'm trying to trouble shoot this 13" MBP, all the power rails appear to be present.
    I see the power supply deliver ~0.58A on boot up then settles to about 0.38A. No boot chime, no screen. All the test voltages appear to be there; however, the PPVCCCPU_S0G voltages never drop fully to 0.6V I'm seeing ~0.83V and ~0.71V on the cpu supply inductors.
    Anybody have any idea if this is indicative of a cpu failure or if there's something I should check.

    There doesn't appear to be any water damage or corrosion anywhere.

    Thanks.
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