in operation macbook A1989 with two dead chips ssd sandisk. I think to replace them with toshiba only these two chips! Is it possible to collaborate ssd of two different manufacturers of chips ssd toshiba and sandisk on one board?
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I replaced all 4 SSD chips from a similar donor, but I still get an error when restoring the DFU. Can you tell me what could be wrong? -
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Some strict rules you have to follow with NAND swaps. You cannot mix them as each chip has data striped across them by Apple. If that data is absent or incorrect, then a DFU restore will fail. So configuration, brand and order matter. More info here:
https://www.youtube.com/watch?v=yR7m4aUxHcMComment
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friends I really need help with images for ssd A1989. I really need itComment
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Hey everyone!
I have a MacBook Pro A1989 with a 820-00850-A board that recently stopped working. I used it overnight to charge my phone, in the morning it didn't turn on, I assumed flat battery but now won't charge and doesn't start at all.
I have fully dissassembled it, when disconnected the battery reads at 0.012V. Even with the battery disconnected the laptop doesn't boot.
The diode voltages around all 4 CD3215's seem fine.
For all CD3215 (UB300, UB400, U3100 and U3200) I read just above 5V on PP20V_USBC_TA_VBUS, 3.3V on PP3V3UPC_TA_LDO, 1.8V... -
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... -
I'm looking to upgrade several 8GB 820-00850 boards to 16GB or 32GB for personal use. I am curious what the best practice and process is for sourcing new replacement chips, and what vendor(s) you guys prefer? Another question is, how do I find compatible chips and their corresponding part/model numbers? For example, in the 820-00850 schematic, the DDR chip U2600 model listed (EDFB232A1MA) corresponds to 1x32GB chip. Of course, I would need 4x8GB chips to replace the 4x2GB chips currently on the board. How do I find compatible 8GB chips? Is it as simple as searching "BGA178 8GB 2133"... -
Today I have a MacBook A1989 at work 820-00850. When assembled, the laptop switches to 20 volts but the consumption is 0.00 ampere. if the motherboard is on the table then the consumption of all ports is 5 volts and0.35 amperes and does not go to 20 volts only if you assemble a MacBook.
Here are some measurements, maybe someone can tell what the problem is.
The initial problem was a burnt out induction coil L8504 (replaced).
When connected to another MacBook, it constantly hangs in dfu and cannot install updates, something is wrong.
here are some measurements
motherboard...
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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
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