FDX40 LA-J261P Power cycling after liquid damage.

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  • eenee
    Member
    • Aug 2022
    • 48
    • Mongolia
    #1

    FDX40 LA-J261P Power cycling after liquid damage.

    Hello guys. I got this motherboard that had liquid damage. The motherboard's type-c controller IC got shorted which resulted in main power rail failing to be produced and after replacement of the IC the main power rail returned. But the board is turning on and off. The current consumption is around 0.120Amps@20volts. After like 10 seconds it turns off and on endlessly. Checking the voltages on the coils:
    pl701-9.04 volts
    plpl101-5.1 volts
    pl201-1.2 volts
    LT1-0(0.685kohms)
    pl301-1.05 volts
    pl100-3.3 volts
    pl614-1.04 volts
    pl402-0.9 volts
    pl613-0 (3.5ohms)
    pl610-0(3.3ohms)
    pl612-0(5.8ohms)
    These measurements lead me to believe the VRM circuit is not functioning properly. I do not understand PWM and VRM circuits very well on this 10th gen motherboard. Guidance needed

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