My brand-new MacBook Pro 14" connected via Thunderbolt/USB-c (with Powerdelivery) in clamshell (closed lid) is not turning on if I power-on the monitor. The monitor is a Dell U2720Q and is providing a 100W.
My previous MacBook Pro, 4 port usb-c (2020 Intel) was able to do this. The Macbook goes on when I turn the monitor on, even when the lid was closed.
Is this a setting or a bug?
MacBook Pro 14″, macOS 12.0
Hi klaas226,
Thank you for posting in Apple Support Communities. From our understanding, your MacBook does not power on with the lid closed when connected to your monitor and the power source is your monitor, do we have that right? Does the same thing occur if your Mac is plugged into it power adapter and wall outlet for power instead of using the display?
Let us know!
1ssmith wrote:
Hi klaas226,
Thank you for posting in Apple Support Communities. From our understanding, your MacBook does not power on with the lid closed when connected to your monitor and the power source is your monitor, do we have that right? Does the same thing occur if your Mac is plugged into it power adapter and wall outlet for power instead of using the display?
Connect a display to your Mac
Let us know!
That's right. My Macbook is off, the lid is closed. My monitor is the power source (USB-C PD 100W) and my Macbook isn't power-on automatically when I press the power button of my monitor. I've to open the lid and press the power button of the Macbook itself to power-on the computer.
My 'old' MacBook Pro 13" (2020 Intel) turns the MacBook on when the monitor switches to on. (same monitor, same cable)
Just tried with Apple wall-outlet adapter connected, but doesn't effect this behavior.
Clamshell mode MacBook power-on by monitor
