HP Envy - keyboard backlight not working

Greetings,

I installed Manjaro 21.1.6 on my new HP Envy I7 laptop. Interestingly the touch screen and trackpad work fine. However, the keyboard backlight isn’t working. I looked up and tried many things on the net. Nothing helped. In fact:

[faye-hp leds]# pwd
/sys/class/leds
[faye-hp leds]# ls -l
total 0
lrwxrwxrwx 1 root root 0 Nov 4 09:07 input2::capslock → …/…/devices/platform/i8042/serio0/input/input2/input2::capslock
lrwxrwxrwx 1 root root 0 Nov 4 09:07 input2::numlock → …/…/devices/platform/i8042/serio0/input/input2/input2::numlock
lrwxrwxrwx 1 root root 0 Nov 4 09:07 input2::scrolllock → …/…/devices/platform/i8042/serio0/input/input2/input2::scrolllock
lrwxrwxrwx 1 root root 0 Nov 4 15:19 phy0-led → …/…/devices/pci0000:00/0000:00:14.3/leds/phy0-led

brightnessctl --list
Available devices:
Device ‘intel_backlight’ of class ‘backlight’:
Current brightness: 19200 (100%)
Max brightness: 19200

Device ‘phy0-led’ of class ‘leds’:
Current brightness: 1 (100%)
Max brightness: 1

Device ‘input2::numlock’ of class ‘leds’:
Current brightness: 1 (100%)
Max brightness: 1

Device ‘input2::capslock’ of class ‘leds’:
Current brightness: 1 (100%)
Max brightness: 1

Device ‘input2::scrolllock’ of class ‘leds’:
Current brightness: 1 (100%)
Max brightness: 1

Any suggestions would be greatly appreciated.

See the Video section here it may be helpful:

https://wiki.archlinux.org/title/HP_Envy_14

Thanks but that link says nothing about the keyboard backlight.

Not sure what I did but the F4 key now correctly activates the keyboard backlight.

Note: that the screen goes black after booting because the backlight is disabled by default. Increase back light using shift-fn-f3 key combination. After installing add command w /sys/class/backlight/acpi_video0/brightness - - - - 1 to /etc/tmpfiles.d/local.conf for turning the back light on automatically.