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Asus Zenbook UX431DA / UM431D - Ryzen - missing PWM Fan Signal.

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    Asus Zenbook UX431DA / UM431D - Ryzen - missing PWM Fan Signal.

    Hey guys.

    Need help with this one.
    Fan not spinning due to missing PWN Fan signal.
    Also 5 seconds from powering up it freezes, unless in BIOS.
    But as soon as Windows starts to load, it will freeze.
    CPU is COLD / Room temp when it freezes.

    I've replaced the CPU, same problem.
    Replaced SIO/KBC IT8987e and reprogrammed - same problem.
    Replaced fan - same problem.
    Replaced flex cable from board to daughterboard (which has fan connector on it) - same problem.
    Checked the Thermal sensors around CPU and Board to the SIO/KBC and they're good too.
    No data lines seem to be missing.

    Checked resistors and data lines from SIO/KBC to the fan, these are good.

    But the SIO/KBC is missing the PWM Signal to the fan.

    If I inject 5v to the PWM, the fan kicks in, but the machine will still freezes when loading Windows.

    What am I missing ?

    Thanks.
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