macOS 11.5.1 Bug: External Monitor Won’t Turn On with M1 MacBook Air
Display issues aren’t new with Apple’s M1-powered Macs, and now it’s gone to a whole new level with our MacBook Air—as in our external monitor doesn’t even turn on anymore.
After updating our M1 MacBook Air to macOS 11.5.1, our trusty Apple Thunderbolt monitor will no longer connect to our laptop. But the monitor turns on perfectly fine when connected to our 2016 MacBook Pro.
We’re not alone in dealing with Apple’s macOS bugs here. Plenty of our macOS M1 Mac users are suffering the same fate in the MacRumors forums.
Add in our M1 MacBook Air still rebooting when waking from sleep (and losing all of our open applications and web browser tabs in the process), I would recommend waiting for an M2 Mac at this point in time. These issues are absolutely infuriating. #earlyadopterproblems
What’s the fix for an external monitor not connecting to your M1 Mac? We tried rebooting numerous times, resetting PRAM, even purchasing a new Thunderbolt to USB-C connector to test–and still nothing.
We may try a full reinstall of macOS as a last resort, but others on the web have said this doesn’t fix the problem and will be a massive waste of time.
But as we said, the monitor turned on immediately when connected to our Intel-based 2016 MacBook Pro running macOS 11.0.1, so the problem lies in this M1 MacBook Air. We did have intermittent issues with our Thunderbolt monitor not turning on before this update, but now we have a major SNAFU.
So now we have a MacBook Air that will reboot when waking up from sleep, plus we can’t use our external monitor anymore. Apple, please fix this or I’m going to buy a Compaq Presario instead (that being said, the M1 is still blazing fast and battery life is excellent).
Update August 16, 2021: After installing macOS Big Sur 11.5.2 fixed our external monitor issues when connecting to our M1 MacBook Air. It’s still intermittent but for the most part (8/10), it’s turning on as normal now.