The Lenovo laptop keyboard not working could also be associated with the outdated or corrupt keyboard driver. This is a toggle switch that turns on and off the backlight.
How to enable the Keyboard Backlight on a Lenovo Ideapad Z400 However, Lenovo makes the “on” button for the keyboard backlight a little hard to find… you have to press the Fn key + the Spacebar key to turn enable/disable the backlight.
Press Fn+ Spacebar to turn on the keyboard backlight.
