I have a MacBook Pro (Retina, 15", Mid 2015) running El Capitan (10.11.6).
It will often run for days with no issue. I will be using the Mac at the time, then suddenly the screen shuts down black as if its gone to sleep (nothing that I've done knowingly has triggered this). There is nothing that I can do to then turn on the Mac - Power button does nothing and pressing the touchpad also does nothing. I have to close the lid and then open it again to wake it up.
When I then open up the Mac, it will stay awake and then repeat the above over and over, only staying awake for 5 - 15 seconds at a time before sleeping again.
I have run:
pmset -g log
.. and i get (amongst all other lines)
Entering DarkWake state due to 'Clamshell Sleep': Using AC (Charge:100%)
From all my Googling, this seems to indicate that the lid has been shut, but the lid is still open.
Any hints on how I can stop this from happening?
ALSO: This is the 2nd MacBook Pro this has happened to, so seems to be a user profile or software thing over a hardware thing. This issue has followed me moving from one machine to another with a Time Machine backup...