A1278 (mid 2012 MBP) - Catalina Firmware Upgrade causing installation failure

[dnivra]

A1278 Mid 2012 MacBook Pro 13 inch (9,2)

During the MacOS upgrade (automatic software update) from Catalina 10.15.6 to 10.15.7, was surprised to see a firmware upgrade.

Post the firmware upgrade, the installation failed.
The same procedure was successful in my other mid 2012 MacBook Pro A1286 (mid 2012 15 inch).

Attempted Internet recovery and it failed at 15 minutes remaining with 'Unable to install Mac OS' error.

Subsequent installation with install disk (USB), I found that the Disk Utility was unable to 'Erase' the internal SSD. First aid returned error 69766 (problem with the EFI system partition's file system).

I cloned the SSD from A1286 and it boots successfully when used in an external USB but fails to boot when used as an internal drive (using the SATA connector).

This made be suspect SATA ribbon cable failure that is common in this variant of MBP but I am able to install Ubuntu and Windows 10 without any problems.

Attempted to install High Sierra, Catalina and even Ventura (using OpenCore patcher) but all attempts failed with 'Bad partition map: Error .

Please help in diagnosing the issue.

Could it be
- problem with SATA cable (common error in this model)
- corrupted firmware
?

Thank you

 

[winxmac]

Try to download Yosemite DMG from Apple and create a bootable flash drive... Use the Disk Utility from Yosemite to attempt to erase the internal storage... Once done, try re-installing Catalina 10.15.7 to the internal drive and see if it will still fail...

 

[dnivra]

Try to download Yosemite DMG from Apple and create a bootable flash drive... Use the Disk Utility from Yosemite to attempt to erase the internal storage... Once done, try re-installing Catalina 10.15.7 to the internal drive and see if it will still fail...

Thank you for your response.

Was able to format the SSD but Yosemite installation failed in the first attempt (with a minute remaining).

Installation of Catalina failed - takes much longer time for Disk Utility to format and the installation stops at 'Less than a minute remaining' stage.

Can the firmware upgrade done during Catalina 10.15.7 be reversed?

 

[winxmac]

Thank you for your response.

Was able to format the SSD but Yosemite installation failed in the first attempt (with a minute remaining).

Installation of Catalina failed - takes much longer time for Disk Utility to format and the installation stops at 'Less than a minute remaining' stage.

Can the firmware upgrade done during Catalina 10.15.7 be reversed?

I am not sure nor do I know if there is a way for downgrading/undoing the firmware update...

In my case, I have MacBook Pro 2015 that was on Monterey 12.3 when I bought it... It took me several hours to download and install but I managed to install 10.10.5 [Yosemite], 10.11.6 [El Capitan], 10.12.6 [Sierra], 10.13.6 [High Sierra], 10.14.6 [Mojave], 10.15.7 [Catalina], 11.7.7 [Big Sur], and 12.6.6 [Monterey] by using a bootable flash drive and no issues...

The only issue I encountered later was not being able to install High Sierra through internet recovery due to unable to contact recovery server... I am not experiencing the issue when installing due to firmware probably because the one I got was already upgraded to Monterey... I went back to Catalina and it is what I am using for I believe it is the best version since it was the last one designed specifically for Intel powered devices...