Is there a special key or value to look at?
It's getting more strange.
After booting in that black screen, plugging in the external display and logging in, I can enable the internal display by pressing the power button several times.
Pressing one time brings no change. I was looking to get this menue to send the laptop to sleep. After pressing the button quickly about 3-5 times the menu appeared and suddenly I the internal screen was working.
But it is not stable. After the next boot I have again only a black screen...
I've done that. But anything changed in the PNLF tab. Does the IOExplorer has an auto update function or must I refresh the view manually after changing something?
Pressing the power button several times while logged in using an external monitor enables all the time the internal display. So there must be a way to fix that. But where to start
What is the expexted value in the ioreg?
I did another check. I change the platform ID back to 0x0166000a which has no slider as it is using eDP. With that value booting runs without any issues.