How to fix a blank screen on Mac after updating to macOS Sequoia 15.5?

Start by deep pressing and holding the power/TouchID button for ten or so seconds to force a shut down. Then press and release it to restart.

If your Mac doesn't turn on - Apple Support

Arjun_sharma202ab wrote:

My macbook is not turning on i have tried everything but it is not turning on neither my ports are bad or clean my cable is alright please help me

[Re-Titled by Moderator]

Original Title: i updated to mac os sequoia 15.5 today and now my mac is blank screen and it is not turning on or off

If your Mac starts up to a blank screen (white, black, gray, or blue)

If your Mac starts up to a blank screen - Apple Support

if necessary you can always force quit a shutdown by holding the power button/TouchID for ~6-10 sec.

Force Shut down your Mac.

Log out, sleep, wake, restart or shut down your Mac

Shut down or restart your Mac - Apple Support