Macbook A1989 - no power

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • tommy97
    Senior Member
    • Mar 2023
    • 167
    • United Kingdom

    #1

    Macbook A1989 - no power

    Hi,

    i've got A1989 after liquid damage, had 2 CD3215 burned (Including primary), i've removed 2nd one and replaced primary with new one - same thing.

    PPBUS 12.25v

    PP3V3_G3H_RTC 3.3V
    PP3V3_UPC_XA_LDO 3.3 V
    PP1V8_UPC_XA 1.8
    PP1V8_SLP 1.8V

    5V 0.200amp on the amp meter - device is not in DFU
  • mon2
    Badcaps Legend
    • Dec 2019
    • 14662
    • Canada

    #2
    Test the LDO voltage of each CD3215.

    https://logi.wiki/index.php/CD3215_Bootup_Sequence

    Comment

    • letsolutions
      New Member
      • Jul 2021
      • 1
      • india

      #3
      ppbus_g3h = 12.25, is it enough?

      Comment

      Related Topics

      Collapse

      • Cemal Odabasioglu
        MacBook Pro A1707 Motherboard Diagnostic Help – CD3215 heating and Fluctuating Rails
        by Cemal Odabasioglu
        Hello everyone,

        I'm currently diagnosing a MacBook Pro A1707 motherboard that does not power on. I've gathered some data but am stuck and need expert advice.
        Note that i'm a beginner in electronics and i'm trying to learn while trying to repair this macbook that my work gave me. I'm really curious and love understanding how thing works and i already learned so much.

        Only one usb c port is taking 20v and have 12.5v on PPBUS_G3H. when trying other ports, 2 are not going to 20v and one is going to 20v but the CD3215 is getting really hot.

        Observations...
        01-14-2025, 03:54 PM
      • MyronViegas
        MacBook Pro 2018 A1989 820-00850-A Stuck at 5.00V and 0.150A
        by MyronViegas
        Hey guys,

        I got a MacBook Pro a1989 820-00850-A dead for repair. The MacBook itself was off for a month or so and it didn't power on. I tested using ammeter and it was stuck on 5v. Opened the machine and found a short on ppbus_g3h, corrosion near the right spkr_amp. removed the spkr_amp and saw short on ppbus_g3h. plugged in to power, boosted to 20v .600A and then back down to .300A. Trackpad was clicking when on .600A but no image etc.

        Later, I tried again but it dropped down to 5v and never boosted back to 20V. checked board again and found ppbus_g3h shorted again....
        10-06-2025, 08:45 AM
      • Madoy104
        Macbook Pro A1989 - No image, working fine with external monitor
        by Madoy104
        Hi everyone,


        I have a MacBook Pro A1989 that was likely exposed to liquid. It doesn't display an image on the built-in screen, but the screen is backlit (you can't see the Apple logo or any other elements when held up to light). The laptop provides 20V and 1.5-2A, and it works fine when I use it with an external monitor. Currently, the connector for the display (J8500) is disconnected. I'm writing to ask for help in diagnosing the issue. I've heard that when the J8500 is exposed to liquid, the processor pin responsible for the display might short-circuit, and I'd like to know...
        08-15-2024, 10:01 AM
      • Stephen
        A1989 Logic Board Repair Issue. One CD3215 chip is the culprit
        by Stephen
        As the title states, got one CD3215 chip being a complete butthole to me. All readings on the other 3 chips read as follows
        5.16V .47amp
        5.16V .47amp
        5.16V .47amp
        5.16V .04amp (this guy is the issue) (U3200)

        So I went ahead and replaced the chip, (actually 3 times with 3 new CD3215 chips) all same issue, at first it wasn't reading at all then it finally started reading. I can rest assured is it not the CD3215 chip now but something else is causing this port to not fully read (god I wish the board would just turn on so we can just recover the data)
        ...
        11-27-2023, 03:57 PM
      • Nikan.e
        MacBook A1989 repair / no CPU voltage no boot signs
        by Nikan.e
        Hello everyone.

        I have recently obtained a MacBook Pro A1989 model with a touch bar and Apple ID. Unfortunately, it does not want to start up.

        No CPU Voltage.
        U7800 Does produce voltages.
        T2 Chip warming up very very little.

        I do have voltages like 1.8, 0.9, 3.3, 2.5 volts, etc., present. I did not find any short circuits. Unfortunately, the device has no touch ID/start button. So, I have used the debug jumper to put the device into DFU mode. - It is getting recognized as a Macintosh while not in DFU mode and as Apple (DFU) while in DFU mode....
        11-24-2023, 11:55 PM
      • Loading...
      • No more items.
      Working...