macOS Monterey 12.3 is bricking 2021 Macbook Pro laptops that had the logic replaced

Pocketnow

By Roland Udvarlaki

Published Mar 17, 2022

The latest macOS Monterey 12.3 update is causing issues for 2021 MacBook Pro users who had their logic boards replaced recently. The update can brick 14 and 16-inch machines, and there's no way to fix it until Apple does.

Source: Pocketnow

Apple released macOS Monterey 12.3 alongside iOS 15.4, iPadOS 15.4, and other operating systems on March 14. The latest update introduced new features such as Universal Control, new emojis, and much more. However, it appears that the latest update is causing issues for users who had their logic board replaced on the 2021 Mac devices, including the 14-inch and 16-inch MacBook Pros.

Several users turned to the Apple support forums asking for help, since many were unable to update, and those who were successful were greeted by bricked machines. Users received error messages, and restart loops when updating from macOS 12.2.1 to macOS 12.3, and some were unfortunate to have their devices completely bricked. Users reported issues after they had their logic board replaced, and it appears to only happen for the 14 and 16-inch MacBook Pro devices, but other machines may also be affected.

An answer was sent to the Apple support forum (via MacRumors):

“There is a firmware bug in Mac OS 12.3 that renders the update impossible to install on any 2021 14 or 16 inch MacBook Pro that has had it's logic board replaced.

The cycle is:

You try to upgrade, the upgrade will fail but recovery to handle it correctly, you'll reboot still on 12.2.1 but with a report a problem dialogue informing you of an iBoot Panic

You'll try to upgrade again. This time, the iBoot FW will corrupt. You'll see the apple icon flash on boot 5-6 times before seeing the exclamation mark symbol telling you recovery is needed.

You can try and revive using a second Mac with Apple Configurator 2. This will fail, because it tries to load the 12.3 firmware from the IPSW, in either DFU or Recovery mode.

The only way to get things running again is to manually download the 12.2.1 IPSW and use Apple Configurator 2, with the Mac in DFU mode, to load the revive image. This will update the firmware of iBoot, and the recovery image to a working build. The Mac will then restore 12.2.1's OS, keeping your data upon finishing.”

Users claimed that they had a possibility of two outcomes after attempting to upgrade the firmware. Users either faced an “iBoot Panic” error message, or were greeted by constantly rebooting and bricked machines.

Users who faced issues with the machine not booting up after updating their devices are required to put their Mac into DFU and initiate the process manually; however, this requires users to have a secondary Mac computer in hand, which isn’t the case for most users. If you are someone who has a bricked device, you’ll have to visit an Apple Store. Users are reporting mixed results, and the machine might not boot after the logic board is replaced again, since there seems to be an issue with the latest macOS Monterey 12.3 update.