Had tremendous liquid damage on this board, I was finally able to get the board up to 12.28volts on PPBUS_AON. I checked the power rails and I know something is off because I'm still getting 5Volts 0.07-0.010 amps This board suffered a lot of damage but miraculously I finally got 12.28 volts! So I know I'm close but its still not powering on, I checked to see if the board was in DFU or recovery since that usually tells me its a Firmware or SOC issue. Nope nothing, tried to force it into DFU and nope nothing. Im kind of at loss here since I am getting power on PPBUS_AON, PP3v3, PP1v2, PP3v8, etc. im like what gives? I feel im missing a small piece of the puzzle. thoughts?
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MEOWING IN THE IMPOSSIBLE UNIVERSE! -
Test the SMBUS lines on the battery which are shared by the same buck / boost regulator here. Test the current loop circuit resistance (without power) that feeds this same regulator. -
SMBUS lines on battery are good 18K on the resistors.sigpic
MEOWING IN THE IMPOSSIBLE UNIVERSE!Comment
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Hi everyone,
I'm working on a MacBook Air 2020 (A2337, board 820-02016) and running into a strange USB-C issue. I've gone through quite a bit of testing and part replacement, but I'm stuck — hoping someone here can shed some light.
🛠 Original Issue
The machine initially wouldn't negotiate 20V over USB-C — stuck at 5V.
Diagnosis showed PP1V5_UPC0_LDO_CORE shorted to ground.
I replaced U3100 (UF400) using a donor board (A2179), and the machine powers on fine now.
⚠️ New Problem: One USB-C Port Only Works in One Orientation... -
Subject: Help Needed: MacBook A1278 (3115) No PPBUS_G3H Issue
Hello everyone,
I'm working on a MacBook A1278 with the 3115 logic board and facing an issue with no PPBUS_G3H voltage. Here's what I've checked so far:- U7000 Measurements:
- Pin 3 has 0V, even though R7012 shows 16.5V from PPDCIN_S5_CHGR.
- Resistors:
- I measured R7010 and R7011 with one leg disconnected, and both tested OK.
Based on these findings, I believe U7000 needs to be replaced. However, I have a related question:- If I also decide to replace the SMC, do I need to order it pre-programmed,
- U7000 Measurements:
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Hello there
I have problem with Macbook Pro 15" 2017, model 2017, MB code 820-00928.
I bought it as broken with some artefacts on the screen, first I thought that this is problem with ribbon cable but after inspectiing ribbon cable I know it is fine. I tried to reinstall macOs and then I figured out that this must be something with GPU as installation freezes at the end (when drivers are loaded). I installed Windows and was able to install every each of drivers except GPU driver, as soon as I tried to install GPU driver - black screen and restart.
...11-21-2024, 05:25 AM -
Just like the title states. I have been confused at this point. Computer won't turn on when lid angle sensor is plugged in, when unplugged it turns on immediately, however I have tried 4 different lid angle sensors all OEM and calibrated without issue. I even pulled one from a donor computer and still nothing. I know the M1 Pro sensors are married to the board however I do know the 2019 intel are not as long as they came from a donor LCD etc. What I do not get is why is the lid angle sensor forcing the computer to not turn on, another issue I see when the lid angle sensor is disconnected...
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I have this MacBook Pro on my bench that I have already fixed, hard short on a SSD rail, but it also has another issue. the right speaker sound is either earrape, muffled or absent. Left one works perfect. I have tried replacing it, nothing changed so I'm pretty sure the issue is either motherboard related or maybe software but I doubt that.
I don't how to troubleshoot speakers. Any help would be very much appreciated.
A refurbisher and a repair shop have already been inside the laptop but I'm pretty sure none of them tried to do any soldering on the board.
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