Apple has fixed an issue that could cause some Intel Macs with a T2 chip to no longer boot up after installing macOS Monterey, the Cupertino firm in a statement. An issue with the T2 security chip firmware prevented some Mac users from being able to start their machines after updating to macOS Monterey.
Apple is now including a BridgeOS firmware update with the existing macOS updates to prevent further failures. Users already impacted by the issue should contact Apple Support for assistance with their machines.
https://twitter.com/reneritchie/status/1456672355992866816
Multiple users found their Macs bricked after updating. Affected users could not turn their Macs on, an issue that affected models with a T2 security chip that controls Touch ID and other security measures. Macs with M-series Apple Silicon-based chips were not affected as they do not have a separate T2 chip.
Macs with a T2 chip were manufactured between 2017 and 2020, with a list available below.
- iMac (Retina 5K, 27-inch, 2020)
- iMac Pro
- Mac Pro (2019)
- Mac Pro (Rack, 2019)
- Mac mini (2018)
- MacBook Air (Retina, 13-inch, 2020)
- MacBook Air (Retina, 13-inch, 2019)
- MacBook Air (Retina, 13-inch, 2018)
- MacBook Pro (13-inch, 2020, Two Thunderbolt 3 ports)
- MacBook Pro (13-inch, 2020, Four Thunderbolt 3 ports)
- MacBook Pro (16-inch, 2019)
- MacBook Pro (13-inch, 2019, Two Thunderbolt 3 ports)
- MacBook Pro (15-inch, 2019)
- MacBook Pro (13-inch, 2019, Four Thunderbolt 3 ports)
- MacBook Pro (15-inch, 2018)
- MacBook Pro (13-inch, 2018, Four Thunderbolt 3 ports)