User profile for user: enriclodi
enriclodi Author
User level: Level 1
4 points

Labyrinth after question mark on 2012 macbook pro

This is for a family member, to squeeze the use of the laptop for a few more months until we decide what to get next. And also, just because is very annoying not to know what is going on...


So the mid 2012 macbook pro randomly showed a question mark after start up. I have tried so many things that by now I am utterly confused and not sure what I have or haven't done, and in what order.


But here are some details:

I have access to a working mid 2012 macbook pro, if it is any help. Same model, same (or very similar) specs.

I have a USB with a bootable 'el capitan' (the original Lion dvds got damaged)

I have changed the hard drive cable (I am assuming the new one is working fine!).

I have access to other hard drives (one HD and one SSD, as well as the original SSD, and also the SSD from the working macbook pro above).

I have run a hardware test and it was ok.

I have run First Aid on the three of them, and they all appear ok, but I know this is not necessarily 100% accurate. However, I am assuming that at least one of them should be working fine. They all show as externals drives (on a USB external adapter) when connected to the working laptop.

One of them even loads the OS as an external hard drive on the working laptop. It goes to the log in, but unfortunately I don't remember those particular log in details, so not sure which OS version it is. In any case, this same SSD does not load the OS on the non working laptop when used as an internal HD.


I have tried the SSD from the working laptop and placed inside the other one, and still does not load (this was before changing the HD cable though).


The hard drives either are not seen by the laptop on start up, or if they are seen, they give an error when trying to reinstall the OS. Basically nothing loads on the malfunctioning laptop. I even tried Ubuntu, and could not finish the install process (before I changed the cable)...


I am also trying to create an bootable Install USB with another (earlier) version of OSX , to avoid a potential problem of installing a newer OS into an older laptop. At the moment it is giving me errors on the different methods I am trying. Seems like a fiddly process, so I giving up unless somebody tells me it is a must.


I have tried many other things (nvram resets etc), many combinations, and often get 'contradictory' results that are driving me crazy. So I think it may be better to start from the basics, follow a step by step from somebody who really knows, so that we can get to some logical conclusion and diagnose the problem.


MacBook Pro 13″, OS X 10.11

Posted on Mar 13, 2025 9:24 AM

Reply
7 replies
Sort By: 
User profile for user: HWTech
HWTech
User level: Level 9
63,572 points

Mar 14, 2025 9:25 AM in response to enriclodi

If a particular drive works fine when booted externally, but is unable to work fine when booting it internally, then there are only four things it is likely to be:

  • Bad SATA Cable
  • Incompatible drive
  • Bad Logic Board (issue affecting SATA controller circuitry, or unable to provide sufficient power to drive)
  • Bad drive


Was the replacement SATA Cable brand new? Usually they have an adhesive strip on them then you must remove the protective plastic covering. If not, then you probably received one that is used or pulled from another system. OWC does sell replacement SATA Cables for this model.


Some SSDs may not be compatible with the SATA Controller on this Logic Board. While extremely rare, even Hard Drives can be incompatible (we actually had a brand new Apple OEM Hard Drive that would not work on the exact Apple laptop it was made for, but worked fine on any other Mac....like I said extremely rare for this happen with a Hard Drive).


Maybe the Hard Drive is wearing out or possibly even failing. While usually you will see the same issues whether the Hard Drive is installed internally or externally, there is always a slim chance of a difference of behavior.


While everything you have mentioned certainly points to some sort of issue with the internal drive connection, I am always aware that these non-Retina models also tend to have issues with the memory slot nearest the Bottom Case. While nothing you have mentioned suggests a memory issue, it is something that I would keep in mind since a bad memory slot could cause the system to freeze or perhaps disrupt the memory just enough to cause a problem.


FYI, here is an Apple article with instructions for creating a bootable macOS USB installer (read the download instructions carefully if you intend to create an El Capitan USB installer since there are multiple additional steps required than for macOS 10.13+):

Create a bootable installer for macOS - Apple Support


How to download and install macOS - Apple Support



Reply
User profile for user: enriclodi
enriclodi Author
User level: Level 1
4 points

Mar 19, 2025 12:26 PM in response to HWTech


  • Bad SATA Cable> It is definitely a new cable, with the sticking side adhesive cover that needs removing etc.
  • Incompatible drive > Is this unlikely, since it had been compatible for a few years?
  • Bad Logic Board (issue affecting SATA controller circuitry, or unable to provide sufficient power to drive)> Is there anything I can do to fully diagnose this possibility without a doubt? Or is it something that is diagnosed once everything else is ruled out?
  • Bad drive > Unlikely, since 'healthy' drives that work externally and/or in the other macbook pro, don't work on this particular machine.


Would a memory problem affect the ssd regardless of whether it is connected as an internal or external drive?


Reply
User profile for user: HWTech
HWTech
User level: Level 9
63,572 points

Mar 20, 2025 7:30 PM in response to enriclodi

enriclodi wrote:

• Incompatible drive > Is this unlikely, since it had been compatible for a few years?

Hard Drive unlikely. SSD....slight chance.


• Bad Logic Board (issue affecting SATA controller circuitry, or unable to provide sufficient power to drive)> Is there anything I can do to fully diagnose this possibility without a doubt? Or is it something that is diagnosed once everything else is ruled out?

Nothing other than what I've already suggested. If the drive(s) work fine when booting externally, then the problem is due to one of the things I listed in my other post.


If you feel really adventurous, then you can try that same drive internally in your working laptop to compare results. Keep in mind you do put that other laptop at a bit of a risk.


Would a memory problem affect the ssd regardless of whether it is connected as an internal or external drive?

Yes. However, if you don't have problems booting from externally connected drives, then I doubt this is the problem. I only mentioned it because of how often I encounter the bad memory slot. Working within the laptop and flexing it may possibly trigger this condition depending on how testing is being performed. It is a slim possibility, but slim possibilities have resulted in long hours of troubleshooting because it really did not seem possible at the time.


Because those 2010-2012 non-Retina laptops had issues with the memory slot nearest the Bottom Case having bad solder joints, an easy test for that issue would be to press on the center of the bottom case where the memory is located. If that memory slot is bad, then it will usually cause the system to freeze and/or have lines appear on the screen. I will even press on the plastic base of the memory slot if the break is not quite severe enough to trigger when pressing on the bottom case itself.

Reply
User profile for user: enriclodi
enriclodi Author
User level: Level 1
4 points

Mar 21, 2025 10:40 AM in response to HWTech

ok, some new data, which contradicts some info I previously submitted, regarding the fact that I had tried the SSD from the working laptop and placed inside the other one, and still did not load (this was before changing the HD cable though).

Today I used the internal SSD from the working macbook, and placed it as an internal drive on the non working macbook, and it worked. So, there is a possibility that the cable was bad, and thus the swap only worked after changing the cable.


However, I still have issues installing mac osx on any of the other drives, and running it on the affected laptop.

I guess it could be that both the cable and the SSDs were all bad. Fixing the cable was only half the job? Maybe. I hope so, but I doubt it.

In any case, I'll get a new SSD and try it again, and report back.


Bellow is what I tried today, which is a bit confusing and full of inconsistent results?


COMPUTER A (the ‘damaged’ one):


SSD A: (as internal) > the drive that stopped working and showed the question mark originally.

When El capitan install:Error on online recovery after apple ID; and error from bootable usb after choosing

target drive install (no packages were eligible for install etc).

SSD A (as external): not seen as a boot option.


 SSD ‘B’: Mac OSX already installed (not sure what version, forgot the password).

External > loads into log in screen

Internal: Seen as option to boot from, but goes to black screen (laptop switches off) after choosing it and

apple icon.


SSD C (Catalina installed):

Internal > it works!


COMPUTER B (the working one):

SSD C Internal > worked fine for years.

SSD C external: not seen as a boot option.


SSD B internal does not start. It goes black (laptop it switches  off after a few restarts. Like in computer A).

External: it loads onto log in screen. However, when trying to re-install El Capitan from a bootable usb, SSD

B does not appear as a target for install.


SSD A:

Internal: When installing el capitan error from bootable usb after choosing target drive install and showing

ETA 13 minutes (no packages were eligible for install etc).

External:not seen in the Boot option at start up.


Reply
User profile for user: enriclodi
enriclodi Author
User level: Level 1
4 points

Mar 23, 2025 3:26 AM in response to enriclodi

Ok, so I have tried a brand new Crucial SSD, and I get the error No packages were eligible for install etc. when trying to install El Capitan from a bootable USB. I suspect it'll be the same when trying online recovery tool (as it has happened with other SSDs I have tried).


So summing up:

A working Crucial SSD with Catalina (from another MBP) runs ok on the 'non working' macbook pro. Thus it is likely that we can rule out hardware problems, and SSD compatibility problems. This leaves the option of a seemingly unsolvable software issue when trying to install OSX. I never thought reinstalling an operating system would be this complicated.

I will religiously follow the Install articles above (again), but I have little hope to be honest. It is really irritating that some dumb software issue is getting in the way...


Reply
User profile for user: enriclodi
enriclodi Author
User level: Level 1
4 points

Mar 24, 2025 5:40 AM in response to enriclodi

Fixed it!

It looks like:

The cable had gone bad.

The SSD had gone bad as well (!)

The Install process needed this (copied from another post):

Restart my MacBook Pro and hold Command+Option+R

until a spinning globe appears after the restart. He said this era of laptops'

certificates for Mac OS X reinstalls have expired, so the option listed above

drives the computer to search for essentially an updated reinstall certificate

online.

Reply

Labyrinth after question mark on 2012 macbook pro

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.
Learn more Sign up