How to turn backlight keyboard on?

Hi,

I am wonder if there is a way to turn on the backlight keyboard on by editing a file or by running a script.
I have a Toshiba M640 with Hybrid Graphic Card Intel/NVidia (upgrade to NVidia was a requeriment to have the backlight keyboard) but I cannot turn it on.
I have an option in the BIOS to turn it on, but as soon as Ubuntu starts loading it turns off.
Any ideas?
Thanks!

Marcelo.

I have the same problem on a Toshiba Satellite A660. Same as OP - lights up during POST, tried setting it to always-on in BIOS, tried Fn-Z. Any ideas? I looked at https://help.ubuntu.com/community/Ma...Lucid#Keyboard but the folders aren't the same, naturally. Looked through /sys/, but couldn't find anything that works.