What controlls backlight intensity K72DR

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  • Sojke
    Senior Member
    • Apr 2017
    • 131
    • Serbia
    #1

    What controlls backlight intensity K72DR

    Hello, can any one tell me how backlight intensity is being controlled?
    I have an Asus K72DR (Rev 3) laptop board which behaves as following:

    100%-70% Normal dimming per 10% and Backlight is on
    60%-0% Nothing visible on screen, backlight is turned off

    Same happens on battery or charger.
    Screen was replaced as well, same thing happens.
    Ive found an boardview of this board but I can not understand anything from it nor find the schematic anywhere.

    The original problem was with the chipset that got reballed and now the laptop works (But with backlight problem).
    Last edited by Sojke; 08-28-2017, 03:29 AM.
    Tags: None
    • Sojke
      Senior Member
      • Apr 2017
      • 131
      • Serbia
      #2
      Re: What controlls backlight intensity K72DR

      EC Controls the backlight via PWM signal, downgrading the BIOS fixed the issue here.

        Comment

        • bachir2004
          Badcaps Veteran
          • Feb 2015
          • 437
          • maroc
          #3
          Re: What controlls backlight intensity K72DR

          reinstalling video card drivers can resolve this.

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