Thank you to the guys at HEGE supporting Badcaps [ HEGE ] [ HEGE DEX Chart ]

Announcement

Collapse
No announcement yet.

HP LA-K321P low res on +5Valw

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    HP LA-K321P low res on +5Valw

    HP LA-K321P short on the +5VALWP line.
    I injected 5V and UA1 (ALC3287) is very hot, after removing it +5VALWP = 5V but the resistance on this line is only 80ohm. If I inject 5V/5A the consumption is only 10mA (80 ohm only on +5valw see picture) but if I try to turn on the board the led turns on for a few seconds and then turns off. I don't know if the card doesn't turn on for 80 ohms or if there is a problem on another component. On the diagram on page 5 looking at the pwr sequence it seems to me that many voltages should be present before the power button is pressed (PBTN_OUT#) is this correct or am I wrong? I thought of a problem with the PCH even if it usually concerns the 3Valw line. Naturally I tried to reprogram the two bios without result.

    MOD Edit: Link to schematic -> https://www.badcaps.net/forum/showthread.php?t=111570
    .
    Attached Files
    Last edited by SMDFlea; 08-01-2023, 12:39 PM.

    #2
    Re: HP LA-K321P low res on +5Valw

    80 Ohms at 5VALW does seems low but its very difficult to findout whats causing it as very low consumption on injection. If you have 10A dc supply, try injecting 5V/10A on +5VALW line and see if it helps. Another way is to manually remove components on +5VALW line to see if resistance increases. I dont see a easy way out.

    PS: Remove card reader,lan chip, usb diodes as well.

    Comment


      #3
      Re: HP LA-K321P low res on +5Valw

      12.6 vb 5valw , 3valw, 1,8valw are present when psu is connected (page 3 on schematic).

      80omh seems low on 5valw rail.
      10mah for 5volt is 0,05 watt.... so no short
      check resistance on j2 jump near u10.
      check u10 if +5vs is on when powered on.
      check pqd11 pqd12 volts on drain source gate to be sure that gate get right voltage for full open circuit.

      Comment

      Working...
      X