Hi, I am working on the Macbook Pro Retina mid 2012, 820-00138-A board. There is no liquid spill on it. I get the Magsafe Green light as normal., Even get the 5V & 3.3V but missing this rail PP5V_S4. 5V should be generated through this rail., but the voltage fluctuates on & off. Check the P5VS4_EN 3.3v, this too is present & after one second it goes, then again it comes back & then again goes out. This is happening on continous basis. Thought that U7501 is faulty & short. Replaced it still the same. P5VS4_EN is coming from U8170. Also replaced U8170 but still the same. PM_SLP_S5_L & SMC_S4_WAKESRC_EN both are acting the same way, voltages comes & goes. I see no short to ground anywhere. Where could the problem be??? Any help would be apprecaited. Thanks
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Re: Macbook Pro Retina mid 2012 820-00138-A
820-00138 board is found on 2015 MacBook Pro 15" IG, not 2012.
What's the history of the machine?
Testing with the bare board on the desk, known good genuine Apple Magsafe2 85W?
Check voltage on CPU VCore and see if it has the same behaviour.OpenBoardView — https://github.com/OpenBoardView/OpenBoardView -
Re: Macbook Pro Retina mid 2012 820-00138-A
Thanks for the answer., yes I think someone must have put another board in it.....or the bottom cover must have been interchanged with another notebook, this is why I see the serial # of Mid 2012. Anyway I will check the CPU VCore voltages but I think I am not using the original Magsafe 2 85W adapter, this is why I have the fluctuating voltages. I will try with 85W adapter tomorrow. ThanksComment
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Hi everyone! I'm trying to fix my black screen / failed U8900 GPU v-core on my Mid-2012 Macbook Pro 15" Retinaby doing a rework/reflow of the chip (once I determine that's the real issue; but it likely is).
I've been disabling the GPU in NVRAM for a few years... but it's just time for a better solution.
I'm new to soldering but the only feasible way to fix this issue is to do something myself.
MY QUESTION:
I've been seeing some people (on this forum mostly) run into issues with the logic board needing a serial number or it being deactivated (?)... -
Good day everyone,
Thanks for all the help and support from this community. I really appreciate them.
I have a MacBook pro Retina 15inch mid 2012 that turns on and get stuck in the loading screen then reboot. There is no sign of liquid damage. The history of this MacBook pro is I got it dirt cheap at a garage sale. so I have no idea about the story behind it.
I was able to extract the Bios dump and it attached to this post to see if someone knowledgeable could help me if the bios is somehow corrupted.
SN = C02J5DCRDKQ1.
Thanks again.... -
Hello, I am looking for any and all files related to the mainboard for 820-2565-A (13" Macbook Pro A1278 mid 2012) schematics/board view.
I looked through forum search results and google and was unable to find a board view file, I found a pdf of all the schematics but I don't know where the parts physically are on the board as this is my first macbook board level repair attempt.
The macbook charger has a green light, the battery has been replaced and OS reports Normal status but Not charging. After cleaning a corroded capacitor it crumbled off the board. There... -
OBDATA Raccoon Computer V1 for Macbook Pro Air 2012-2025
It's the end of three years of work, it costs money, it costs time, and you owe me a beer.
This is the new database for FlexBV
it's optimized to work with it
by using board ID has Default name, give us the opportunity,
to use other diode board data with sibling board or family board
I Merged the whole data (optimal)
A2991 A2992 M3 -> -> 2 Entries diode data M1
A2681 A3113 A3114 M1 M2 Air -> -> 2 Entries diode data M1 M2 13"
A2442 A2485 A2779... -
Hi all. I am working on MacBook Pro (Retina, Mid 2012) A1398 820-3332-A. There is no liquid spill & no physical damages on the logic board. The CPU/GPU heats sink heats up a lot & then turns off automatically. I did a re-solder job on the GPU VCORE chip U8900, but this did not help much & also updated the BIOS. Added brand new coolant compound but still the same, after about 1/2 hr, it heats up & then turns off automatically. Just asking anyone will the CPU & GPU BGA balls reflow will be suitable to rectify this problem. Any tips or help will be greatly appreciated. Thanks...
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