Hi to all i have a faulty a1990 from 2018, no liquid damage, died during update, now on configurator i see recovery not dfu, and i get error 9. caps around u7701 show short after removing u7701 and shorted caps still short. can any help.
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With your meter in the lowest resistance scale -> what is the exact resistance to ground of the caps noted with a short condition? If it is a low power rail, the resistance will be low by design. -
Also, be sure that you are using a quality usb cable for the dfu process. Keep it short as possible but quality- we use a cable rated for 40gbps sourced from Amazon.Comment
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I'm getting 195 omsComment
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I have use a short type c still same resultComment
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195 ohms is fine for a RAM rail. T2 has to boot before you even get into the Intel power sequence where these rails are activated.
Review the power sequence for CD3215/CD3217 on Logi wiki. If the T2 firmware is corrupted, it stops at PMU_PVDDMAIN_EN. USB C consumption should be 5V 300ma if that is that the case. Rule out T2 firmware corruption before messing with hardware!Comment
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One reason DFU will fail is shorted SSD power rails as these are quite common on A1990. Most common failures are C9091, C9093, C9087, C9098 on one side, C9586, C9588, C9589, C9593 the other. The caps are exposed to high air flows from fan intakes and often corrode.Comment
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Thanks, ive check all caps mention all good. this is a 2tb so it has all ssds populated.Comment
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on PMU_PVDDMAIN_EN, im geting 3.3vComment
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As it's in recovery, something failed in the loading of the Intel EFI process. Make sure you have 2.5V etc on power rails for the SSD's on either side. You should force it to DFU and then attempt a revive, then restore if that doesn't work.
If that all fails, you likely have an issue around the T2 PMU, the T2 itself, or bad NAND's.Comment
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I tried using Configurator. When I try to do anything it just reboots to recovery with no option for terminal. I'm not sure if it is also icloud locked however I do not think so. Do I have any options? -
Hi,
my MacBook Pro 15" 2018 Touch Bar (A1990) doesn't charge anymore. Board# 820-01041-A
I'm not experienced in diagnostics, but I want to try to solve the problem with your help, because every local shop charges around 600€ (650 usd). Which is the value of the whole Macbook.
The Macbook was charging when suddenly the "charging sound" appeared every other second for around 4-5 times.
After that the Macbook was dead. It isn't charging anymore.
The USB-C Port where the charger was plugged is burned. Also The Cable and the... -
Hello, i have a batch of 10 Macbook Pros A2179 bought from a Costco return wholesaler.
The 10 of them show the exact same behavior;
They auto power on, to internet recovery spinning globe, fans to 100%.
Power consumption on USB-C port is 0.43a, shuts down as soon as unplugged. Battery doesn't charge at all. However, it boots to 20V on the Ampmeter.
Based on their iBridge versions (4.x and 5.x) these were shelfed for a long time.
All of them power on the same way; 100% fans, shut down as soon as they are unplugged. Removing... -
I have an M1 MacBook Air (A2337) 2020 that came in for water damage and will not turn on. Upon opening it, I saw that the audio board was severely corroded. I disconnected it, and the device started working.
After that, I dealt with the issues on the audio board by removing the capacitors that were shorted to ground, and the device started working. However, I encountered another problem: I can't access the recovery options by pressing and holding the power button. I'm not sure if it's a hardware issue or if the recovery partition has been lost. Currently, the system's time isn't updating,... -
So, i dont know almost anything on macs..but this is my nephews so i had to try. Its 16 inch macbook pro from 2019...It all started when he left something on the keyboard when closing the mac and there it was the crack on screen. At first it was like working but later no. After that he told me that it wouldnt power on?...hear fans but nothing..tried like 100 of stuffs but nothing helped.
So, he bring it to me...first i open it and figured he did also. there was lots of dust i cleaned everything...and started it...the broken screen showed only backlight but nothing on the screen. I...
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