12-15-2018 02:41 PM - edited 12-15-2018 06:49 PM
I suddenly was unable to adjust the brightness on this 3-day-old laptop. Moving the slider from zero to 100% using the keyboard wouldn't adjust the light. (I don't have adaptive brightness.)
It seems that rebooting will return the ability to adjust the brightness. However, without fail, once the laptop wakes up from sleep one cannot adjust the brightness again using the top row of the keyboard. Nine times out of ten, however, if I use the brightness slider under Display Settings, that will work.
EDIT: I've updated bios and other system updates using Lenovo Vantage. I checked lighting adjustment after waking from sleep, and it seemed to work fine this time. Hopefully, I was panicking needlessly. Will keep an eye on it.