2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

[cyber16]

hello everyone,
I had a couple few 2018 Mac minis come in from a local church, the majority of them showed no life and it was no issue DFU and recover the ibridge software.

I have this last one that has been recovered, immediately goes to Internet recovery downloads and then reboots and goes right back to Internet recovery. OR there have been times it would reboot bring up Apple logo and the progress bar but it would never start populating that progress bar and we just hang there.

I have tried every conceivable method including trying to boot to an external macOS drive etc. The T2 chip/icloud is not locked, it is clear.

I have even imaged a clean install from another identical Mac mini and wrote that to this problematic hard drive via target mode and that fails

I brought it to Apple and they ran test and everything showed to be functional yet they were unable to resolve the issue/restore, other than suggesting a new logic board at nearly the cost of a new M2 Mac mini.

If I start this particular machine in target mode I can write to the hard drive no problem with another Mac. After many attempts of internet recovery I had noticed that recovery is not creating the base partition.
I even tried local macOS install of several versions.

So my question is two part, is there an easy method to actually disable the 512GB SSD drive? Maybe something like removing a component? and additionally once that is done do you think it would be possible then to proceed with an install on a external hard drive now that no longer sees the internal?

[ktmmotocross]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

why dont u just replace that ssd?

[stj]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

why dont u just replace that ssd?

it probably doesnt have one.
knowing apple they probably just put an ssd controller and some flash on the mainboard.
or maybe the soldered one in without a connector somehow - you know they dont like people doing upgrades.
a pcb picture would help

[ktmmotocross]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

it probably doesnt have one.
knowing apple they probably just put an ssd controller and some flash on the mainboard.
or maybe the soldered one in without a connector somehow - you know they dont like people doing upgrades.
a pcb picture would help

i know. but he still can replace chip

[hasefroch]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

What happens if you boot in diagnostic mode? IIRC, should detect this kind of hardware failure.
If you leave completely blank the internal disk, that should stop the system to try to boot from it.
You can do that via target disk mode; if not able to leave it blank, just partition and format it in something that the mac will not recognize as bootable, like MBR and ExFat.
This should let you boot from a external system disk without problems, if the internal SSD was 'locking' at boot.

[cyber16]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

I have already erased the SSD which is in fact chips and controller on the logic board. I have erased it and left it uninitialized, I have formatted it fat 32, and every conceivable other format methods in hopes it would be ignored.
Not sure exactly where the issue is, but it definitely is missing its standard macOS base system volume, and that is not even created during the attempts of Internet restore recovery.
Since Apple has done away with target mode installs I can't use another device and install macOS on this internal hard drive.
As I mentioned I have done a complete clone of a fresh install done on an identical Mac mini and it would fail the boot. Although it has tried a couple times.

I'm at at a loss in the next few days I can post a image of the logic board.
My thinking is just maybe once the internal SSD driver it's not seen maybe I can do an install to an external.
At this time all it is is a power-hungry external target mode drive.

[hasefroch]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

First of all, do not use Internet Recovery.
Build a USB Installer in another mac following these instructions:
https://support.apple.com/en-us/HT201372

Boot from that installer pressing Option + Power, then do the install on a external disk (leaving blank the internal SSD, just in case).

Still, I would see first what happens when you run the integrated diagnostics (press the key D when powering up).

[cyber16]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

I have done that multiple times with multiple versions of macOS with the same results.
Even with a bootable USB install thumb drive it will not work.
I have been working with both macs & PCs for well over 30 years. It's been my self-employment business, owning a computer shop building machines going on the way back. It's too bad apple got rid of the target mode install starting with high Sierra due to the fact High Sierra introduced the new format and requires firmware updates, it would have been nice to be able to try that method.

One other tidbit of information I forgot to provide, one power is applied it'll automatically turn itself on and try to boot and only brings up the blinking folder with the link to Apple.
There is no chime at power on unless I reset pram, but it will only chime after a pram reset. If I press and hold the options it automatically brings up the Internet recovery.

As I stated in the first post the T2 chip is clear of any prior accounts but I'm thinking just possibly there's an issue with it, but when Apple connected to it at the store and tested they had seen no issues whatsoever with the logic board but also failed to do an install for them, they had it for several days trying all kinds of things. They're only answer at that time was to replace the logic board at nearly the cost of what I new M2 mini would cost. I have DFU recovered the ibridge software for the T2 multiple times to completion.

Hence the reason I should try to disable the SSD controller in a reversible manner to see if that will allow me to install to external which would be fine since I do have some rather quick thunderbolt drives.

Diagnostic reports no errors, that was one of the first things I had tried and forgot to mention.

edit: the link to iFixit has the teardown of this unit including pictures of the logic board and component layout.
Except with the differences that my particular Mac mini has an i7 6 core and 500 gig SSD
https://www.ifixit.com/Teardown/Mac+...eardown/115210

[stj]

Re: 2018 Mac Mini with bad internal SSD "Possible to disable SSD?"

if you want a quick and dirty way to disable microcontrollers, just link the pins on it's crystal - if it has one.
maybe the board has a "lifeboat" jumper.

btw, if you can boot a linux live image then try looking at the ssd SMART data.
maybe it has reached it's write-count limit and is shrinking.