Hp Lh482p 5 short 3 long short after cpu vcore mosfet replacement

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  • jm942
    New Member
    • Jul 2024
    • 2
    • Belgium
    #1

    Hp Lh482p 5 short 3 long short after cpu vcore mosfet replacement

    Hi,
    My laptop went dead and after checking ,the main 19 volt power rail was shorted. After some checks i could identify that a high side vcore mosfet was shorted.
    I replaced the mosfet and now the white powerled is present , fans start spinning but capslock shows the famous 5 long and 3 short code.

    I checked the vcore voltages after replacement and i get for all 1.01 V so means for me that the driver is still working of the replaced shorted mosfet. On the Nvidia i measure around 0.8 V after the mosfets.
    I did voltage injection on the cpu with 0.7V and i have a current of around 300 mA.
    When i measure the resistance vcore to ground i have 0.9 - 1 Ohm.

    Based on this i think my cpu has survived but what can be the reason of not starting the laptop then ?

    Any suggestions , something i can check additionally to be sure my cpu gives signs of life ? As far as i can see i think all voltages needed are present like 3.3v,5v,19V


    Tags: None
    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      High side VCore mosfet shorted=Killed CPU. You'll still get the vcore voltage and it'll behave like display is about to come but the wait is forever. thats the classic symptoms of a killed cpu by 19V.

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