MacBook Pro 13" Unibody Mid 2012 A 1278 Hard Drive Cable

My Problem

After having a 500 GB SSD installed, the MBP was unbearably slow to boot up and respond. The repair shop gave it last rites and returned it to me. It booted so slow and responded so slow that I was not able to do any productive work on it. I tried multiple solutions unsuccessfully, and I saw where iFixit cited the possibility of a damaged hard drive cable.

My Fix

I followed Goldheart's directions to the letter. The guide was comprehensive, and I didn't have any trouble following step by step. (I forgot about taking pictures. Next time for sure.) I sheathed the broad section of cable in electrical tape to protect it over the long haul.

When the repair was done, the MBP loaded and responded quickly. I reinstalled Mac OS, and this Pro is now running Catalina beautifully.

My Advice

If you are new at this like I am, read the guide through more than once and even give it a walk-through. Also read the comments from other people who know what they are doing. I think I spent as much time reading as I did hands-on.