Bricked MBP 2015 Catalina install. Boots to question Mark folder. Corrupt BIOS? EFI?

[goldminer76]

Hello I saw a video by Louis that addresses the issue of bricking your Mac when installing Catalina. My understanding, please correct me if I'm off, is that Catalina leaves a file that is 32bit on a 64bit system.

Here is what I got from the video. Please tell me if I'm off:

Many Macs are being bricked. Apple is deleting solutions on the support page. The actual issue is this.

Apple removed 32 bit software in Catalina but kept a 32 bit program for entitlement management on the machine.

The offending app is located here: /System/Library/PrivateFrameworks/IMTranscoding.framework/XPCServices/IMTranscoderAgent.xpc/Contents/MacOS/IMTranscoderAgent

Solution(s)

For T2 Macs. if you see black screen yet hear power and chime there is a possible fix that has worked.

If you can get into super user mode (command + S when booting) or Internet recovery mode then use terminal then you could do these commands:
disenable root (enter password) /sbin/mount -uw / rm -rf /System/Library/PrivateFrameworks/IMTranscoding.framework/XPCServices/IMTranscoderAgent.xpc/Contents/MacOS/IMTranscoderAgent disenableroot disable Now this only works when you can actually get to a Terminal screen via Super User mode or Internet Recovery. But I'm dealing with a 2015 Macbook Pro that will not get there. I see there is a Medusa tool that can clean ME but can't FlashRom on a Raspberri Pi do the same thing. I already have adapters for the boards.

I see a post on this forum on how to flash EFI but it seems old.

My questions are:

1. When talking about this issue, what is the correct terminology? Am I working with the bios or EFI or what?

2. If this is corruption of the BIOS, Do I just need to clean the ME region to get the BIOS working again? Will Catalina Boot after this is done?

3. Can I do this with FlashRom and a Raspberry Pi?

4. Is the issue actually on the Bios/EFI chip? It looks like from the Directory above the issue is an application in the OS. Does this application kill the bios/efi (forgive me if I'm saying this wrong) on older than 2016 Macs and is not just as simple as deleting the file? Because I can't get the board to boot from anything. Just goes to question Mark folder after like 30mins

 

[2informaticos]

Try clean ME BIOS first, to discard that problem.
You can find on the forum how to clean it manually.
You can probably find a link for clean ME BIOS already posted; but I don't know which board you have.
If not, upload your backup somewhere...

 

[goldminer76]

Can't seem to find the post for clean ME BIOS. Lots of talk about Medusa but I'm pretty sure it can be done with a Raspberry Pi and Flash Rom no? When you say back up do you mean the bios? Is there a guide on how to back that up?

 

[goldminer76]

It looks like FlashRom is for older bios possibly and not UEFI. I have a Raspberry Pi 3+ and I even have Ghostly hacks UEFI lite with the adaptors. I see a tutorial on Ghostly hacks that shows how to clean the ME region using HXD or similar program. What I'd like to know is how to get the Raspberry Pi with adaptors connected to the board and the program on my PC to talk to each other and enable this process?

 

[goldminer76]

I found this tutorial for SPI ROM

https://boards.rossmanngroup.com/fo...ite-erase-apple-efi-spi-rom-with-raspberry-pi

Can I do this with the 2015 MBP? Do I need to isolate the chip (take it off) or can I just use the debug connector with my adaptors?

 

[KC Micro Tronix]

The bios with the T2 chips requires the bios chip be removed and soldered onto a level splitter as they don't use 3v3 logic anymore. The T2 is a whole new animal. If this was a A1466 I would agree with cleaning the ME. In this case I think it is a rabbit hole.

 

[2informaticos]

You have a 2015 machine, why do you bother with T2 theory?
Instead of losing time reading such, take out U6100, read it and upload the file.
You didn't even post exact model of the board yet.
Not easy to find needed file this way.
You must know what to search at least...

 

[Alan.L]

seems like a bad ssd to me.

 

[goldminer76]

You have a 2015 machine, why do you bother with T2 theory?
Instead of losing time reading such, take out U6100, read it and upload the file.
You didn't even post exact model of the board yet.
Not easy to find needed file this way.
You must know what to search at least...

Hi, Sorry I forgot to post the board, it is a 2015 Macbook pro 820-00138-a (Non T2) I guess I wanted to discuss all the fixes for this Catalina issue but you're right I should just stick to this board. What I was trying to figure out is would the solution posted above work for non T2 macs but it looks like it doesn't.

I can find posts here on the forum about Cleaning the ME with MEDUSA and about how to flash BIOS with Flashrom and Raspberry Pi but are they the same thing? Becuase I can't seem to find a "how to" on cleaning the ME region. Just posts stating that you should. I see some info on how to clean ME on Ghostly hacks but they don't say how the computer connects to the board.

So I hope that someone can tell me if I can connect a PC through a Raspberry Pi to the board with the EZ connectors I got from Ghostly hacks and how to do that.

 

[goldminer76]

You have a 2015 machine, why do you bother with T2 theory?
Instead of losing time reading such, take out U6100, read it and upload the file.
You didn't even post exact model of the board yet.
Not easy to find needed file this way.
You must know what to search at least...

Hi you're right! What hardware software do I need to read the board ( 820-00138-a ). Do I need to take off U6100 or can I do it on the board with the connectors I have for my Ghostly hacks EZ Flash lite? If you know what that is, it's the EFI password remover and comes with connectors that go onto the debug port (?) These connectors can attach easily to a Raspberry Pi.

 

[2informaticos]

No idea about Ghostly hacks tool.
If you can access the BIOS this way, read and upload it.
Untill get your backup clean, you can try known good clean ME BIOS, if you find...

 

[goldminer76]

No idea about Ghostly hacks tool.
If you can access the BIOS this way, read and upload it.
Untill get your backup clean, you can try known good clean ME BIOS, if you find...

The Ghostly hacks tool just comes with adapters that clip onto the BIOS header just like the MEDUSA 2. (pic #1)


. The EFI Destroyer lite (Ghostly Hacks) uses a Teensy arduino board to with adapters which can access the BIOS. It's used to remove firmware lock. Much like the SOIC or SOP clip of old, the adapter accesses the BIOS chip through the "header" (pic #2) while on the board. What I can't find is how all of the group here is downloading the BOIS and reflashing known good clean ME BIOS on boards Again I see posts about MEDUSA but I would love to tinker around and make my own MEDUSA. So I guess I need to ask a more direct question.

1. What tools and software do we use to read and write clean ME BIOS to a 820-00138-a? If you could provide links that would be swell.
*I've found raspberry pi and SOIC8 POMONA clip and for software FlashRom

2. Is this boards BIOS accessable with SOIC8 POMONA CLIP? Or can I access it through the header with adapters I already have just like what the MEDUSA comes with?
?

Thank you again for all the help. I've run into this issue more than once. I

 

[2informaticos]

You must connect to J6100, to access SPI chip.
Cheap Pomona clip is not the best tool to use.
Forget about it, if you have the correct adapter for J6100.

Do NOT quote an entire post, visible few centimeters above.
Please maintain forum aesthetic...

 

[goldminer76]

Not sure what you mean by "do not quote entire post" should I spread the quoted sentences out? Then answer the questions asked in the quoted post individually? I was just trying to comment on the quoted text in order. Sorry if that's not the way to do it.

You say connect to the J6100. That's the header right ? lIke in the picture I posted. I do know how to connect to that but I appreciate your reply. My question was about the software to use and the device (computer or whatever) that is needed to read and write to the bios. I see posts about the need to clean the ME but I could not find how to. I think I might have it figured out but I thought someone here might be able to steer me at least in the right direction. The responses I am getting make me feel like I'm not asking the right questions? Or are we not allowed to talk about it on this forum? Just want to make sure I'm following the rules

 

[goldminer76]

2informaticos I REALLY APPRECIATE your help. I know that while this is a paid forum people don't really "have" to help you at all. So you have my gratitude! I am just going a little stir crazy trying to get an answer on what people are using tool and software wise to clean ME. Should I ask this question in another part of the forum?

 

[2informaticos]

You need to access SPI chip (U6100) through J6100 connector.
I have no idea really about the mentioned tool.
I supposed that you know how to use this tool, if you bought it.
Must have some software, which allows to read/write the SPI chip.
Or the adapter just connect to any BIOS programmer.

I told you to upload BIOS backup of your board, to get it clean.
Is the fastest way to help here.

If you want to learn more about ME region, read there
https://www.win-raid.com/t1658f39-G...-CS-TXE-Regions-with-Data-Initialization.html
We also have in the forum short explanation about how to do it...

 

[goldminer76]

Ok I've figured out how to program a raspberry Pi 3 b+. I have a connector. How do I get a clean dump for a 2015 Macbook pro 820-00138-a ? Serial Number C02RKE3TFVH3. Will I need to edit the serial number when reflashing?

 

[2informaticos]

"I told you to upload BIOS backup of your board, to get it clean.
Is the fastest way to help here."
Is the third time now...

 

[goldminer76]

Facepalm sorry. Will do that.