We recently had a customer performing a Logic board swap on a 2012 13" Retina Macbook Pro and we ran into a very interesting problem. I think it would help allot of people out so I thought I would share what we discovered.
Our Customer installed his original SSD and the system would not boot or recognize the installed SSD. After a phone call with allot of trial and error we realized the issue, was the File System.
The SSD had macOS Mojave (10.14) which we reasoned was using the new Apple File System (APFS), which was introduced with High Sierra (10.13). It turns out the board we had sold was never used with High Sierra and thus did not have the needed Firmware update.
Thankfully our customer had a time machine backup of their Mac and we where able to walk them through doing internet recovery reformatting the drive and restoring using time machine.
This solution should apply to all Macs using SSD's that originally shipped with MacOs Sierra (10.12) or lower.
Its also a great reminder of how easy and useful Time Machine can be.