w540eu no power(3v 5v missing)

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • ashan000
    Member
    • Jul 2022
    • 34
    • Sri lanka
    #1

    w540eu no power(3v 5v missing)

    I have no power board(w540eu). no 3v 5v presents.. checked ic pins. EN pin only show about 1v.. according to schematic, I guess EN not generate by io chip. I attach pdf files and voltages presents.

    see the image plz.
    no voltages on the gate 1 of the mosfet(DD_ON signal) is that the problem.??
    Attached Files
    Tags: None
    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      Re: w540eu no power(3v 5v missing)

      Does SIO releases DD_ON??

        Comment

        • ashan000
          Member
          • Jul 2022
          • 34
          • Sri lanka
          #3
          Re: w540eu no power(3v 5v missing)

          Originally posted by mcplslg123
          Does SIO releases DD_ON??
          No it does not.. does SIO need VDD 3 to work..??

            Comment

            Previous template Next

            Related Topics

            Collapse
            • maneatingmonkey
              Missing LCD Panel Voltages VGH, VGL, VCOM (TCL 55P6US Sound & Backlight but NO Picture)
              by maneatingmonkey
              I have a TCL 55P6US with sound and backlight but no picture. This model does not have a T-CON board, and the right (rear perspective) panel board is fed from the left panel board. I have not been able to induce any change by disconnecting the secondary panel board or the tape cut-off method on the primary board.

              There are a bunch of voltages missing on the panel boards. I can't find any shorted caps of the panel boards, and all of the missing voltage rails read in the kiloohms, which leads me to suspect the issue may lie on the circuit board, rather than a short in the panel.
              ...
              L Panel #1
              11 Photos
              03-27-2024, 07:17 AM
            • karlp028
              MSI Z390-A PRO missing VCORE voltages
              by karlp028
              I've got an MSI Z390-A Pro motherboard that starts up fine, but it's missing the VCORE (and VGT) voltages. All of the other voltages are present (e.g. VCCSA, VCCIO) and I know the CPU (i7-9700k) is good. Now, the original PWM controller (UP9521P) had an internal short and I replaced it with a new one. All of the enable signals look good. The problem seems to be the PWM signals going to the MOSFET drivers. I checked them with an oscilloscope and they are all flat 1.5V with no pulses. I don't know why this would be and I'm not sure where to look next.
              06-23-2025, 01:25 AM
            • mat2k
              Lenovo 300-15IBR - No SYSON, no SUSP#, bunch of missing voltages
              by mat2k
              Hello, I've been struggling with this one today. I'm troubleshooting a Lenovo 300-15IBR (board BMWC1/BMWC2 NM-A471) that turns on the power LED and does a bit of fan spin but nothing else. 3v3sb and 5vsb present, no 1.05v, no 1.35vddr, no vcore, no 1.8vsb.
              BIOS has been reflashed with one I found here, supposedly tested OK by someone else. I don't have an EC programmer unfortunately.
              I looked around and SYSON is 0v, SUSP# is 0v too. Forcing them to 3v3 enables the 1.35v rail, but the 1.05v and 1.8v rails are still missing (generated by PU704). EN_1P05A signal is 3.3v, and IN_1P05A...
              12-01-2024, 11:00 PM
            • Capacitorial
              Powersupply has all the voltages - Monitor still no power
              by Capacitorial
              Hello guys,

              I have a Philips 240B7QPJEB. The monitor seems completely dead.
              I opened it and measured the voltages of the powersupply. I found that a mosfet was dead and replaced it.
              On the connector, that goes to the TCON board, all voltages 15-19V and 5V are present.
              The small connector on the left of the PSU has two cables with 18V and all the other have 0.2V. It connects on this small connector on the left ontop of the panel. I guess the backlight? Seens fine I guess.
              The weird thing is, that the Power LED is powered over the TCON board.
              On The TCON...
              12-28-2024, 02:12 PM
            • redbomb65
              msi mpg z390m gaming edge ac missing voltages and wont turn on when pressing the power button
              by redbomb65
              hi i have a msi mpg z390m gaming edge ac mb. that wont turn on when i short the 2 pins on the front connectror.
              im new in electrionic repair. and i hope that someone will share a bit knowledge, thoughts or ideas with me and others, to repair that damm thing ;D
              1. thought psu problem. nope psu is good. i even bought a psu tester to be save.
              2. thought a short somewhere that the psu goes in short save mode. nope... no short to measure with my multimeter to ground. psu and mainboard starts with all cabels plugget in, when i bridge green and black on the 24 pin.
              cpu isnt...
              01-24-2024, 08:36 PM
            • Loading...
            • No more items.
            Working...