Apple’s second macOS Monterey 12.3 beta, released on Tuesday, appears to fix a battery drain during sleep issue that began with the release of macOS 12.2 to the public last month. The issue was apparently due to Bluetooth accessories frequently waking up the machines, draining the battery.
Users report that disabling Bluetooth on their Mac or disconnecting all Bluetooth accessories are disconnected from the Mac fixes the issue, but this is not really an ideal solution.
Affected users found that their Mac’s battery life dropped from 100% to 0% while in sleep mode overnight. A few users investigated in Terminal and found that Bluetooth accessories were frequently causing a “DarkWake from Deep Idle” that saw the Mac repeatedly waking from sleep and draining the battery.
However, a tweet from Mr. Macintosh said that his 2018 MacBook Pro, which was experiencing the issue on the first beta of macOS 12.3, is no longer showing the same issue after installing the second beta.
From what I can see, macOS Monterey 12.3 Beta 2 (21E5206e) fixes the Bluetooth battery drain issue.
I tested 3 times & didn't see a single DarkWake 👍
1. 2018 MBPro that had the issue on 12.3 B1
— Mr. Macintosh (@ClassicII_MrMac) February 8, 2022
macOS 12.3 will likely see a public release sometime around March or April, which will hopefully include the apparent fix for all affected Macs.