External monitor goes black when I close the lid

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Level 1

4 points

External monitor goes black when I close the lid

Hello dear Apple community,

Recently bought myself a Macbook Pro M3 Pro and updated to Tahoe right away.

Problem is, I can't seem to make my external display work properly : It kinda works when lid is opened (extended mode) but once I close the lid in order to only use the external monitor, it just goes black.

I can see the monitor is still on but stays black.

Also, I'm using an HP Dock station with a high end thunderbolt cable and the monitor is the iiyama PL2770QS (monitor settings have been reset already).

Can someone please help me ? :)

MacBook Pro 14″, macOS 26.0

Posted on Oct 8, 2025 3:18 AM

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Answer 1

Top-ranking reply

neuroanatomist

Level 9

53,787 points

Oct 8, 2025 8:13 AM in response to DqdOuu

To work in clamshell mode, your Mac needs to have an external keyboard, external mouse or trackpad, and be connected to AC power. If your dock provides power over the TB3 connection, that should be sufficient.

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Answer 2

DqdOuu Author

Level 1

4 points

Oct 9, 2025 2:38 AM in response to neuroanatomist

To work in clamshell mode, your Mac needs to have an external keyboard, external mouse or trackpad, and be connected to AC power. If your dock provides power over the TB3 connection, that should be sufficient.

A bluetooth keyboard (Mx Keys S) + wired usb Logitech mouse are connected and I've tried already plugging the Apple charger on top of the device being connected to the dock. Screen remains black whenever I close the lid..

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Answer 3

CT

Level 7

24,221 points

Oct 8, 2025 8:09 AM in response to DqdOuu

Maybe this:

Can MacBook Air M4 work in Clamshell mode… - Apple Community

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Answer 4

Oct 9, 2025 7:43 AM in response to DqdOuu

<< I can't seem to make my external display work properly : It kinda works when lid is opened (extended mode) but once I close the lid in order to only use the external monitor, it just goes black. >>

What do you mean, "kinda works" ??

if you mirror the external display with the internal display, then close the clamshell, they are both tied together and the external will correctly reflect that the internal is now blanked.

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