Replacement of the secondary HDD in a MBP 13" mid 2012

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Replacement of the secondary HDD in a MBP 13" mid 2012

I have to replace the secondary HDD of my MBP 13 "mid 2012 because it is faulty. It's a 512 Gb HDD 2.5" 5400 rpm Sata I ( it was the old Apple main HDD). I bought a 512 Gb 2.5" 7200 rpm Sata III HDD to replace it. The main SSD (System Disk drive) was installed some time ago, in a Caddy in the place of the SuperDrive, in the Optical bay. I installed the HDD I bought mentioned above, but it does not mount. Utility Disk detect it but after very long time, and the System boot is very slow. It fails to mount it. I have verified that the hdd is working and the system detect it perfectly when I put it in a usb external case. My MBP running on High Sierra. Is It possible that the new installed HDD is not compatible? Would anyone have a solution? Thanks

Posted on Mar 10, 2021 7:55 AM

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Answer 1

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HWTech

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Mar 12, 2021 8:45 AM in response to Garma67

Garma67 wrote:

Now that I think about it, however, a doubt arises me. If, as you say, the flat drive cable is faulty, how is it possible that the old Hdd that I should replace, as I noticed by installing it later, is instead detected and mounted (even if it’s faulty due to bad sectors)?

The hard drive SATA Cable in this particular model laptop has an extremely high rate of failure. The failure is so bad that Apple even had a free repair program (now expired) where Apple proactively replaced this cable even if there were no apparent issues with the cable. I've personally seen this cable fail with different symptoms on our organization's Macs.

As @Grant mentions an SSD is transmitting a lot more data at much faster speeds across that cable so you need a much more resilient cable than one used with a hard drive. With some of these cable failures even a hard drive won't be able to work correctly. Perhaps your hard drive is suffering from the cable defect but you don't notice it because the drive is so much slower to begin with. Have you confirmed the hard drive has bad blocks? Perhaps what you assume to be bad blocks is the cable causing problems. It wouldn't surprise me an original Apple hard drive on a 2012 system is worn out or actually failing.

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Answer 2

Mar 10, 2021 8:12 AM in response to Garma67

did you replace the drive cable when you replaced the drive?

The drive cable is a weak point, so weak that many suggest replacing the cable when replacing the drive should be thought of as "routine preventative maintenance."

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Answer 3

Mar 10, 2021 3:29 PM in response to Garma67

No, a new cable will not work the same way.

The one you have has failed, as evidenced by your using the drive just fine in an external enclosure, but failing inside your Mac.

The new one will actually work.

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Answer 4

Mar 11, 2021 7:14 AM in response to Garma67

That sort of drive, in sizes up to 8 million TeraBytes, has been handled since MacOS 10.4 Tiger. it's not drive incompatibility.

The MacBook Pro operate perfectly fine, but negotiates the speed down to SATA-2 transfer speeds.

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Answer 5

Garma67 Author

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Mar 10, 2021 12:53 PM in response to Grant Bennet-Alder

No, I didn't think about replacing the drive cable because I didn't think it was faulty. The old hdd in fact was detected and mounted without problems (although it's unusable and not initializable due to bad disk sectors). So do you think it is necessary to replace the flat cable? And if so, which one exactly should I buy? Same as the one to be replaced? Will it work the same way with a 7200 rpm Sata III Hdd? Thank you in advance

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Answer 6

Garma67 Author

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8 points

Mar 12, 2021 2:05 AM in response to Garma67

Now that I think about it, however, a doubt arises me. If, as you say, the flat drive cable is faulty, how is it possible that the old Hdd that I should replace, as I noticed by installing it later, is instead detected and mounted (even if it’s faulty due to bad sectors)?

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