Simon, is there perhaps a Dell software utility for this? Then it's probably not in the 9550 either. You can change keyboard backlight brightness, not timeout. I don't know about 9550, but that option isn't in the BIOS for my 9560.
On my 9570, that sets the keyboard backlight to 'always on'. Look in the UEFI BIOS under 'System Configuration', 'Keyboard Backlight Timeout' for AC and battery, set to 'Never'. Does anyone know if there is a clever way to achieve this? I cannot find away to do this with my 9550.
