Why does my built-in display turn off again after a Shortcut reconnects it?

Check whether Disconnect built-in display when an external display is connected is enabled. On Apple silicon, this rule can disconnect the built-in display again after a Shortcut or CLI command successfully reconnects it, while a qualifying external display remains connected.

Open Settings > Displays > Overview > Display Connections > Connection Management Settings… and turn that option off if you want your automation to choose when the built-in display stays connected. Then run the Shortcut again. Switching the Shortcut from Toggle to an explicit On does not override the automatic rule.

Why the menu switch can behave differently

Reconnecting the built-in display through the app’s menu temporarily suspends automatic disconnection and shows a notification. The Shortcuts Connect or Disconnect a Display action and CLI connection command do not apply that same temporary suspension.

To keep the automatic rule but limit which external monitors trigger it, configure their Ignore for built-in display auto-disconnect exceptions. See automatic built-in display disconnection for setup.

See Display Connections for the rule’s requirements and recovery safeguards, and Shortcuts for creating the action. This explanation applies when the display comes on and is then disconnected again. A display that cannot reconnect at all needs a different diagnosis.