where is the backlight dimmer?

[Carney]

Mike...Would not accept the fn key or any f key. Maybe my function keys are disabled.  I learn something new everyday Thank you  Dan

I have this problem too.

I can get change screen brightness fine with a Fn and F5 or Fn and F6 keystroke, but I'm trying to find a way to eliminate the need to hit the Fn key, and just make the F5 and F6 keys act by default as if the Fn key had been held down.