Asus TUF LED monitor VG27AQ power cycling

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  • sixstringartist
    Member
    • May 2012
    • 18
    • USA

    #1

    Asus TUF LED monitor VG27AQ power cycling

    My asus LED monitor VG27AQ is power cycling. I see backlight come on, displays logo and then shuts off and repeats.

    When I power it on, it draws ~200mA (@19V) before turning on the backlight. It jumps to 1.6A for a few seconds then Im guessing the processor goes to standby as it drops to a trickle (8mA). Each of the coils have voltage on them, none are short to ground. The diodes on the small board (LED driver?) look good. Im not seeing any significant hot spots under a thermal. All that really lights up is the two nearby coils labeled 2R2 when the draw ramps up to 1.6A, then off. None of the caps look obviously bad to me, but I could try removing/testing/replacing some. Im not sure what to look for next. Any help would be greatly appreciated. ​
  • lotas
    Badcaps Legend
    • Jan 2016
    • 4589
    • Russia

    #2
    The power supply itself (19V) supports the load; when switching to operating mode, the voltage does not drop?
    Also check the signal lines (relative to ground) of the hdmi and dp ports for resistance.
    Last edited by lotas; 11-15-2024, 03:42 PM.

    Comment

    • sixstringartist
      Member
      • May 2012
      • 18
      • USA

      #3
      Originally posted by lotas
      The power supply itself (19V) supports the load; when switching to operating mode, the voltage does not drop?
      Yes the power supply supports the load. There is not a drop when it switches to the 1.6A draw. The problem is present when using a benchtop power supply as well as the original power adapter.

      Comment

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