Lenovo GS452/GS552/GS752 NM-C781 pulsing power led

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • AndyBNoobTech
    Member
    • Sep 2022
    • 12
    • United Kingdom

    #1

    Lenovo GS452/GS552/GS752 NM-C781 pulsing power led

    Hi guys, I have searched for this particular issue for the NM-C781 board but all I could find were schematic and bios requests, so apologies if this has been asked before.

    I've got the above board from a friend, it appears to charge ok but as soon as you press the power button, the LED's on the side and on the button itself just flashes. I have checked around the board, there are some low resistance values to ground on some of the coils, mosfets and capacitors but they are not dead shorts (3.7 to 5 ohms) so im not sure if that normal.

    I was wondering if anyone else had come across this issue and what they did to rectify it (if it's even fixable). I did read that the issue could also be caused by bad BIOS, I'm still waiting for my eprom programmer to arrive.

    Thanks guys and gals

    Andy
  • mon2
    Badcaps Legend
    • Dec 2019
    • 13846
    • Canada

    #2
    Re: Lenovo GS452/GS552/GS752 NM-C781 pulsing power led

    Hi. See attached.

    Carefully measure and post the voltage readings of the charger IC pins (highlighted) with the power adapter connected and logic board turned ON.
    Attached Files

    Comment

    Related Topics

    Collapse

    Working...