PSA: If your Mac logic board has been replaced, don’t update to macOS Monterey 12.3
Apple released macOS Monterey 12 in late 2021, introducing new FaceTime and Safari features, in addition to other improvements. Since then, the company has been working on further enriching the operating system. Earlier this week, the Cupertino tech giant released macOS Monterey 12.3 — the latest update to this major version. It brings the long-awaited Universal Control feature and supports the new Unicode 14.0 emoji. It additionally comes with a nasty surprise that affects some unlucky users. Recent online reports indicate that updating to macOS 12.3 on Macs with replaced logic boards could brick them.
Users on Apple Developer Forums have been complaining about the latest macOS 12.3 update. Some of those who have had their Mac’s logic board replaced are reporting endless loops and other issues preventing them from using their Macs. They’ve highlighted the details of the process below:
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.
It’s unclear if Apple is aware of the issue at this point. However, it’s safe to assume that the company will eventually patch this serious bug. In the meantime — if you’ve had your Mac’s logic board replaced — refrain from updating to macOS 12.3.
Did updating to macOS Monterey 12.3 brick your Mac? Let us know in the comments section below.
Source: Apple Developer Forums