Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • justin35
    Senior Member
    • Jan 2019
    • 149
    • It

    #1

    Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

    Mbp 820 2936 board
    Laptop came in with no green light.
    Pp3v42 was shorted to ground. It turned out to be isl 6259.
    I injected 2v@1amp on pp3v42 line and u7000 got worm.
    I replaced u7000 and the board post has chime but not charging battery.
    U7000 pin 17/18 3ohms pin 27/28 20ohms
    Ppbus_g3h is 12.27v !!!
    Green light appears after 3-4seconds it flickers a few times then it's solid green and fan starts to spin.
    I tried to run ads test but it get stuck on loading asd ... board freezes mouse light goes off
    I did reflow smc, no luck
    Changed again u7000, no luck
    I reballed smc, no luck
    Smc data lines for u7000 are ok...
    If i plug in battery+magsafe, when i disconnect magsafe, it runs from battery...
    I never encountered this problem, ppbus 12.27 instead of 12.5+v and board posts

    Thanks!
  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

    Could be bad SMC.
    Is battery percentage correct in macOS?
    Did you check PPBUS_G3H with battery and BIL disconnected?
    SMBUS diode mode measurements are the same within 1% for both SDA and SCL?
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

    Comment

    • shibu
      Member
      • Apr 2016
      • 28
      • uae

      #3
      Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

      hi can you check without connect battery the pp3v42 is there

      Comment

      • justin35
        Senior Member
        • Jan 2019
        • 149
        • It

        #4
        Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

        I could not load os, because is very slow... so i don’t know if the battery percentage is there.
        It even doesn’t load ads from usb...
        Ppbus measure without battery and bil connector installed and unistalled ... (same voltage)
        Sda scl in diode mode red probe on ground 0.57 and 0.47 so there is like 20% percent difference?!?
        One resistor measure 1998ohm and one 1820 ohm... swapped the lower resistor with a 1950ohm but it’s also pulled down to 1800ohms because of the circuit...
        I think is the smc?!

        Thanks!!
        Last edited by justin35; 07-01-2019, 12:23 PM.

        Comment

        • piernov
          Super Moderator
          • Jan 2016
          • 4435
          • France

          #5
          Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

          Yeah if you measured diode mode with everything disconnected, it's probably the SMC itself. (since charger IC has been replaced already)
          OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

          Comment

          • justin35
            Senior Member
            • Jan 2019
            • 149
            • It

            #6
            Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

            Charger ic was replaced twice... from donors boards... i refuse to believe it had the same fault ...
            I'll try to find an other smc

            Comment

            • qonma
              Kuli Solder
              • Jun 2017
              • 184
              • INDONESIA

              #7
              Re: Macbook pro 820-2936 not charging ppbus 12.27v - strange it posts

              This problem solved???? I have same problem....only can on with battery

              Comment

              Related Topics

              Collapse

              • tobeend
                Bypass mdm macbook m2 ventura
                by tobeend
                1. RESET MACOS WITH IPSW

                a. Power off MacBook, press and hold the power button to enter Recovery
                b. Open Disk Utility, remove Macintosh HD
                c. Reboot, connect to the network to Activate Mac.
                d. Plug the C cord in the first port of the MacBook into the other Mac, then power off the MacBook
                d. Hold down the Control (L) + Option (L) + Shift (R) + Power key combination for 10 seconds
                e. Release the other keys, but keep holding the Power key for another 10 seconds
                f. MacBook is returned to DFU, open Apple Configurator 2 on the other Mac, right-click...
                05-26-2023, 07:18 AM
              • SarcasticOP
                General question about MacBook power rails for repair.
                by SarcasticOP
                I am looking at an A2337 and found this for the order of power rails and what they do. Can this be confirmed before I dive into hunting down power rails that do not exist or are not neccisary?
                • PPBUS_G3H (12.6V-12.8V)
                  • This is the main power rail that supplies power to the entire system. Check this rail first, as it must be present for other power rails to work.
                • PP3V42_G3H (3.42V)
                  • This power rail is derived from PPBUS_G3H and is used to power the SMC (System Management Controller) and other essential circuits. It should be present if PPBUS_G3H is working correctly.
                • PPVRTC_G3H (3.3V)
                  • This
                ...
                12-12-2024, 05:50 PM
              • JM1010
                Macbook A1707 short on PPBUS - nothing gets hot
                by JM1010


                After using a bad charger (cord chewed by dog...) Macbook died.

                Getting 20V and oscillating 0 and .2amp on amp meter

                PPBUS is shorted (.8V)
                After checking resistance with Vcore (ok), injected 1 amp, then 2 finally 3 amp on PPBUS and nothing seems to get hot except the PCH (barely tolerable to the touch at 3amp.)

                If I can't detect anything getting hot @ 3 amp, what else can I do??

                Thanks in advance.
                12-18-2021, 08:31 PM
              • obelix24
                A2941 Macbook air 15” - 5V 0a
                by obelix24
                I’m working on one macbook air 15” m2 that was water damaged.

                keyboard, lcd, microphone connectors were damaged so i’ve replaced all of them and without screen connected macbook worked fine. Keyboard &trackpad and also lid sensor was working fine.

                i’ve put macbook in shelf and order new screen so i can fully repair it.

                Now i got the screen and macbook stays at 5v 0a.

                i’ve tried if it’s not in DFU with another macbook but it’s not detected at all.

                i don’t have schematics so i don’t know where to start can someone help me?...
                03-27-2025, 01:19 PM
              • Instafixx
                Macbook A1466 820-00165 PPBUS Missing
                by Instafixx
                Hello, I have a Macbook A1466 80-00165 which is not turning on. It is taking 0 ohms and the PPBUS_G3H is at 0v at F7140.

                Tried Injecting 1V but nothing gets hot.
                Removed the F7140 fuse and the Pin#2 is still short to ground.

                Can anyone suggest where the issue is ?
                05-20-2023, 06:42 AM
              • Loading...
              • No more items.
              Working...