Macbook Air 2018 A1932 Bootloop

Collapse
X
Collapse
+ More Options
Posts
 
  • Time
  • Show
Clear All
new posts
  • Clarify4082
    Senior Member
    • Oct 2022
    • 61
    • USA

    #1

    Macbook Air 2018 A1932 Bootloop

    Hi,

    I have a A1932 Macbook Air with Bootloop.

    I already replaced the battery with a new one and reset NVRAM and SNC.
    When I start the Macbook the Screen is coming on (no Logo) and switches of after a few seconds. If I start without the trackpad and keyboard it stays on longer.

    If I use diagnostic (Option+D), recovery (Option+R) I always get the Apple logo and it go into online-Recovery. Even if I boot the installer from a USB-stick it ends up in online-recovery. Sometimes it crashed short after entering the wifi password, sometimes it loads the recovery but when it finished it restarts again. see here: https://streamable.com/vef2f9
    I can´t get into DFU-Mode because it shut´s down before it enters the DFU state

    Other than the CPU the T2 chip get´s warm/not hot.

    Behavier is the same when I disconnect the power-button and display.
    Also no signs of damage or liquid on the board...

    Any ideas what I can check next?
  • mon2
    Badcaps Legend
    • Dec 2019
    • 13969
    • Canada

    #2
    1) Be sure the power adapter is beefy enough to power the unit. Suggest 100W USB Type C with a certified 100W rated cable.

    2) Use a USB Type C meter to gauge the voltage and current draw from this logic board. It helps to understand the condition of the board.

    3) Review the voltage to ground of PPBUS_G3H. Post the measurement. If this measurement is low, then remove all power and measure the RESISTANCE to ground of the same rail to check for a short.

    Comment

    • Clarify4082
      Senior Member
      • Oct 2022
      • 61
      • USA

      #3
      1. Only have 65W charger, try to get a 100W tomorrow
      2. Please see the video. (Everything is attached, Battery, Touchpad...) https://streamable.com/949728
      3. Voltage in PPBUS_G3H is 12.25 - 12.70V during a boot cycle. Not sure what it should be...
      Click image for larger version  Name:	image.png Views:	0 Size:	283.3 KB ID:	3543408
      I also have diode readings, as seen in other threads
      Click image for larger version

Name:	image.png
Views:	45
Size:	1.07 MB
ID:	3543415
      thank you!

      Comment

      • mon2
        Badcaps Legend
        • Dec 2019
        • 13969
        • Canada

        #4
        PPBUS_G3H is 12.25 - 12.70V
        It is in the proper range.

        https://logi.wiki/index.php/PPBus_G3H

        Do you hear a boot chime?

        Comment

        • Clarify4082
          Senior Member
          • Oct 2022
          • 61
          • USA

          #5
          yes, everytime it starts up

          Comment

          • Clarify4082
            Senior Member
            • Oct 2022
            • 61
            • USA

            #6
            Maybe the replacement battery is also bad?
            I get 1.2V (slowly dropping) on PPBUS_G3H when the charger is not plugged.

            Also I cannot start the Laptop when only the battery is plugged at first time. I need to connect the charger, than it powers on. After that I can unplug the charger and the laptop starts with battery.

            Comment

            • Clarify4082
              Senior Member
              • Oct 2022
              • 61
              • USA

              #7
              Update: Get it into DFU mode now. Unfortunately there is Error 4005 and 4042 witch indicates a problem with the ssd

              Comment

              Related Topics

              Collapse

              • netboy69
                Macbook Pro 15, A1990 2018, showing recovery not dfu, error 9 when restore, HELP
                by netboy69
                Hi to all i have a faulty a1990 from 2018, no liquid damage, died during update, now on configurator i see recovery not dfu, and i get error 9. caps around u7701 show short after removing u7701 and shorted caps still short. can any help....
                02-07-2024, 04:34 PM
              • bouch
                unlock macbook air A1932 2019
                by bouch
                hi

                i whant unlock macbook pro A1932 2019 whit ibridge 9,3 ;

                i change efi files find on files mina T2 activator 1,4 and use for activation mina T2 activator 1,3 , but fault ssh?

                i use mina T2 ramdisk activator 1,0 and 3,0 . but whon t work ?

                have you other programme or method compatible whit this macbook ibridge 9,3 for bypass ?

                I need help or information?

                Does anyone have the minat2 activator 1.4 software?

                Or did they use it for bypass macbook air 2019 a1932 with new ibridge 9.3?

                Thank yo...
                03-12-2025, 10:14 AM
              • reessi
                Macbook Air - 2018 - A1932 - 820-01521-02 - Bootlooping if Power Button Connected
                by reessi
                Hello,

                With the power button connected it either boot loops with the apple logo or no display but the charging meter shows it looping on charging every few seconds.

                No corrosion any where!

                Tried a replacement power button off ebay and the same.

                Very occasionally it will work with the power button connected!

                Same results with or without the battery.

                Can it be a fault with the Audio board or the mainboard?

                The touch Id assembly connects through the Audio board first then to the Mainboard.

                Flex...
                06-26-2024, 03:31 PM
              • sikocan
                MacBook Air 2018 A1932 820-01521 Not turning on.
                by sikocan
                MODEL: MacBook Air 2018 A1932 820-01521

                Problem: 5.12V / 0.60Amps

                History: Unknown but I can see slight liquid spill on IC U8201/74aup1t97gm

                Things tried: I've cleaned the liquid area, removed the IC U8201/check pads, good/ chip looks good, put back. Replaced CD3215C x 2 times, so 4 new chips just in case. I've attached photo readings of V/resistance and signals as per logi wiki website. Please advise what I can check next. Schematics available upon request....
                08-05-2022, 06:47 AM
              • mitchw
                MacBook Air 2018 A1932 820-01521 stuck at 5V, but succesfully does the DFU and boots into OS installer
                by mitchw
                I have a 820-01521 that is stuck at 5V, and drawing just 230mA.
                I did some troubleshooting, and managed to charge the battery up (was at 0%) using a different logic board.
                Also I ran DFU and it did it successfully. Had to use a PMU_FORCE_DFU jumper to do it.
                At this point the laptop started up and it successfully boots into the OS Install.

                The charger is now at 20V, but drawing 0mA, so the laptop is essentially running off the battery. It doesn't detect the charger...

                I think there could be a problem with one of the CD3215s, but all the LDOs are the...
                01-04-2024, 01:47 PM
              • Loading...
              • No more items.
              Working...