I'm having trouble with the internal display of my Thinkpad Edge E525 Laptop:
The display stays black and now I'm trying to find out whether it's defective or did I somehow deactivate it?
- The screen turned black after I accidently entered the command
lightdmin a terminal emulator (the command was supposed to be issued in a ssh session...) - I then tried to get it back by pressing all possible button combinations (including the function keys)
- I couldn't bring it back, so I did a hard reset by pressing the power button for some seconds
- Even the hard reset had no effect. The moment I entered
lightdmin the terminal, the screen went black and stays black
What I already did to check for a display defect:
- The screen is absolutely black. My guess: no backlight problem.
- I connected it to a secondary display and that works perfectly! My guess: no graphics card issue.
My Questions are:
How to diagnose a problem with the internal display? Is there a way to tell whether the screen stays black because of the user or the (defective) hardware?
Important: Most probably there is no connection between lightdm and my problem, but I didn't want drop this detail.