2012 Macbook Pro won't recognize new SSD after (presumably) a HDD failure.

Aside from your reply to a 3 year old question (which I hope the OP has resolved long ago), I would trust Apple's instructions far more than anything on YouTube:

https://support.apple.com/en-us/HT204063

https://support.apple.com/en-us/HT201295

Hi. I was having the same problem with HDD only my Mid 2012 MacBook Pro was going very slow and over heating so I bought a new HDD tried that out and was still having the same issue. I just installed an SSD drive booted up in recovery mode and formatted the new hard drive and re installed OS. Now my computer started to run faster and cooler than ever until a week later I started getting that grey screen as if t wasn't reading the new SSD. So long story short here I put in a new Hard drive flex cable and problem solved mac runs like new and faster.... It's an easy fix

A couple of observations:

1. A visit to the Apple Store Genius Bar is free of charge. Best to make an appointment as they are often busy.

2. This particular Mac, the mid-2012 13" MBP, has a known issue with the hard drive cable failing over time, often after 3-4 years. If you are short on cash, this is something you can do yourself. Cables and instructions are available from PowerBook Medic and ifixit. It's a fairly simple procedure, and shouldn't be too expensive even if you have someone do it for you.

Good luck!

I recently had this same issue. I brought my Mac to the Apple store and the genius bar told me this was a common problem on mid-2012 MacBooks. There is a bracket holding the hard drive that fails, causing the cable to the hard drive to fail. Believe it or not, Apple has recognized this issue and the repair was completely covered under a warranty, even though I brought mine in 5 years after purchase. They sent my laptop out to get fixed, and I got it back in the mail the same week. I didn't spend a dime for anything.

Thanks for the info. I have the same problem but Apple says they do not solve the problem since June 10. So annoying :-(

Anybody can please tell me how to buy the piece and any explanation how to replace it?

Many thanks in advance from Spain.

You might try OWC:

Apple 821-1480 Hard Drive / SSD Cable For... in stock at MacSales.com

I believe they ship world-wide and there might be an installation video. If not, ifixit will have instructions. It is not a difficult project.

Good luck!

Isadiohc,

your Mid 2012 MacBook Pro didn’t come with an installation disc, so that’s of no concern.

If you reïnstall your Hitachi HDD, you could try the following steps to see if they would repair it: boot your MacBook Pro into Recovery mode by holding down a Command key and the R key as it starts up. Once the OS X Utilities menu appears, select Disk Utility. On the left-hand side of the Disk Utility window, select your internal disk’s boot partition (typically called “Macintosh HD”). On the right-hand side, select the First Aid tab if it’s not already selected, then press the Verify Disk button if it’s not greyed out; if it is greyed out, or if it reports that errors were found, press the Repair Disk button. Once the verification/repair is completed, exit Disk Utility and select Restart from the Apple menu to restart in normal mode. Does it get past the grey folder with the flashing question mark now?

There’s a chance that your internal SATA cable is faulty, but there’s no firm evidence yet that that’s the cause of the problem. Do you have access to another Mac? If so, buy a SATA-to-USB adapter (they’re not expensive), and try connecting your SSD externally to the other Mac, running Disk Utility there to reformat your SSD. Once it’s been reformatted, try reïnstalling it in your MacBook Pro to see if OS X Internet Recovery will properly download your MacBook Pro’s original version of OS X from Apple’s servers.

Did you format your new drive Mac OS Extended (Journaled) and set it to GUID Partition scheme?

Well, it can't detect it because it doesn't have an OS installed and it's not formatted. Do you have a bootable clone you can boot from? If so, boot from it and use its' Disk Utility to format your drive.

FWIW, taking it to the Genius Bar is a good idea; getting a ? means the drive can't find the system. It might (or might not) have been easy to fix: simply boot into recovery and repair the drive. Or there may be other problems. In any case, if you cannot access your old HD, you can try recovery. Not sure if it'll work: hold down Command + Option + R while booting up until you see a progress bar and spinning globe. It'll take a while to connect to Apple's servers. Once you see the Utilities window, choose Disk Utility and format the new drive. If that works, then choose to reinstall the OS.

I upgraded my MBP to an SSD: I installed the new SSD in an external enclosure, plugged it into the MBP, formatted it and cloned my system to it. Then I switched the two hard drives and was able to boot up from the new SSD instantly since it had been formatted and my system installed on it. So, if you can boot up from your old hard drive, I'd try that method. Or take it to the nearest Genius Bar (take both drives with you).

In that case, I think the Genius Bar is your best bet.