Keyboard backlight not working

Hardware Librem 13/15
1

I have a used Librem 15 v3. Pressing the F10 key does nothing while all the other function keys work. Is it common for the keyboard backlight to stop working?

1 Like
2

Are you pressing Fn+F10 (not just F10)?

1 Like
3

Yes i am pressing both Fn+F10. Should the keyboard backlight work before PureOS 10.3 loads, while i am still in SeaBIOS, or only after the operating system is up and running?

1 Like
4

Yes, it does work for me in SeaBIOS. If you remove the bottom shell, it looks like the keyboard backlight is the leftmost flat ribbon cable (edge of the mainboard near the battery). You could check if it’s fully seated. Be careful as those ribbon cables and connectors are delicate.

If that’s not it, then you may need a replacement part - I believe we have some parts for Librem 15 but not every part, support@puri.sm can help you check on a part. We’d also want to figure out whether it’s the mainboard or keyboard, probably we could check whether there’s power on the keyboard backlight connector with a voltmeter (but be careful not to short the pins with the voltmeter probes of course).

1 Like
5

There does not appear to be any loose cables.

Librem 15 v3
Librem 15 v31333×1000 229 KB

1 Like
6

Agree, it looks like the keyboard backlight connector is seated alright (leftmost in the photo). It does occasionally help just to try reseating it though.

Do you get any voltage on that connector? The left two pins are negative, the right two pins are positive. If there’s no voltage, press Fn+F10 and check again since we don’t know whether the EC has the keyboard backlight on or not. If there’s still no voltage, you’d probably need to replace the mainboard. If there is voltage in any of those states, then it’s probably the keyboard.

Also I’d put some tape over the ends of the Wi-Fi antenna cables (which appear to be broken off), you don’t want those bare leads to touch other stuff and short things out.

1 Like
7

I do not have a voltmeter right now but i may be able to borrow one. I will try reseating the cable later because the bottom shell is already screwed back in place. Thanks for your help.

1 Like
8

My keyboard backlight stopped working one day on my Librem 14.

1 Like