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    A2337 M1 MacBook Air stuck in boot loop

    No luck. I get the exact same errors with the LCD disconnected. I did connect the charger cable before the DFU cable (I'm using a white Apple USB-C-to-C charger cable). Target laptop does take current from charger - switches between 0.4 and 2.22A at 20V (mostly at 2.22 except while rebooting). I...
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    A2337 M1 MacBook Air stuck in boot loop

    I have an A2337 M1 MacBook Air that had coffee spilled on it, but there was no liquid at all visible on the logic board or audio/power button board. The laptop was stuck booting to the boot options menu, and if I tried to pick Macintosh HD it would pause, then reboot back to the boot options...
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    820-00840-A (2017 13" MBP) PPBUS_G3H at 1.1V, USB at 20V but 0.04A flowing, No Power or Charge

    Found EN_VR1, as you said it's on the schematic. My boardview has it labeled as "PM_EN_P3V3_G3H". Voltage: 3.39V The two USB-C port certainly do NOT have the same behavior. One does not even light up my power meter, and board voltages are very low (compared with what I've been posting here from...
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    A2141 820-01700 No LCD Backlight; 55 ohms between PPVOUT_S0_LCDBKLT and ground

    I forgot about this thread after fixing the machine - just wanted to say thank you. The short to ground in this machine was indeed one of the capacitors in the set of C8460-73. I replaced it with a capacitor from a donor board and the machine worked perfectly. Thank you so much!
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    820-00840-A (2017 13" MBP) PPBUS_G3H at 1.1V, USB at 20V but 0.04A flowing, No Power or Charge

    > Why continue doing that??? Sorry, I must have misunderstood, I thought that was one of the things you wanted me to test, when you said stop to check ohm scale or diode mode with power applied to board. By "power applied to board", did you mean the method of injecting 1V? Measuring between...
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    820-00840-A (2017 13" MBP) PPBUS_G3H at 1.1V, USB at 20V but 0.04A flowing, No Power or Charge

    (I typed this a few days ago and apparently never hit Post!) R7020 appears to be an SMD component who's terminals I can't access. Measuring the lines connecting to it, though, all 4 of them are at 19.98V. With the USB-C cable connected to what would have been the rear port in the laptop, I get...
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    820-00281-A 2017 15" MBP Fan Control Transistor Q6000 broken, doesn't work after resoldering

    I have a 2017 15" MacBook Pro motherboard (820-00281-A) where the transistor in the fan control circuit (Q6000) accidentally got broken off the motherboard while doing a board swap into a new topcase. Result was that when I turned the computer on, the left side fan would run continuously full...
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    820-00840-A (2017 13" MBP) PPBUS_G3H at 1.1V, USB at 20V but 0.04A flowing, No Power or Charge

    I have a 2017 13" MacBook Pro motherboard (model 820-00840-A) that won't turn on. I measured the PPBUS_G3H line with a USB-C charger connected, and get around 1.08V (instead of 12V?). No short to ground in this line - resistance measures 1K ohms rapidly increasing to infinity. Fuses F3000 and...
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    A2141 820-01700 No LCD Backlight; 55 ohms between PPVOUT_S0_LCDBKLT and ground

    Alright, I'll try that. What's a good voltage to start with, to inject after removing L8452? Also, when I desolder the capacitors, what temperature do I need to keep the hot air machine at, and what distance away from the board is best?
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    A2141 820-01700 No LCD Backlight; 55 ohms between PPVOUT_S0_LCDBKLT and ground

    Hello, I have a 2019 16" MacBook Pro (A2141) with no LCD backlight (the laptop does power on, boot to macOS and display stuff on the screen, but the backlight is off so you have to shine a light at the screen to see anything). I tested the PPVOUT_S0_LCDBKLT line at the terminals of L8452 and...
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