Bizarre "fix" Losing ability to change brightness of screen

[everalm]

For no readily apparent reason, my shiny new SP 2017 has lost the ability to change the brightness of the screen.

Swipe from the right to the Action Centre.....brightness button doesn't change anything

Access power icon...nope

Control panel.....nope

Rummaged on line, usual suggestions, re-install the drivers for both the Surface monitor and the Intel Display driver....nope

Came across a registry tweak

Disable Intel Display Power Saving Technology on Surface Pro 4

Worked...yippee...for 2 days then back to where we were and the registry setting doesn't change anything....

Any suggestions.....?

 

[everalm]

It appears that the issue is related to a combination of the keyboard and the the machine going on hibernation when the keyboard is closed

To "fix"

When powered on, detach the keyboard
Power off via the touchscreen
Power on without keyboard
Log on without keyboard
Reconnect keyboard
Machine screen power now works

Weird

 

[theveterans]

^ Wait for firmware upgrades, but it would be helpful to let MS know about that on their feedback app.