I've just installed Ubuntu 16.04 on my Lenovo Z400 notebook and everything was working. Today I tried to change the brightness of the screen and it gets dark and I can't go back. Can anyone help me?



I faced the same problem before on my laptop Lenovo z500 ideapad after searching i found this solution :

  1. open terminal
  2. sudo nano "/etc/default/grub"
  3. append acpi_backlight=vendor to the GRUB_CMDLINE_LINUX_DEFAULT line:

    GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
  4. save and close nano (Ctrl+X, then confirm saving changes)
  5. sudo update-grub
  6. restart

If nothing changes , you can check the solutions of this question.

  • This does not work for ThinkPad P50 on 17.10. – Sander Verhagen Feb 8 '18 at 10:05

protected by Community Dec 12 '16 at 7:59

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.