I have ASUS G551JM with the same problem (the Fn+F5 and Fn+F6 keys do not even get registered by the
I found the following workaround solution: to map another pair of Fn+ keys into a custom brightness script. I choose to use
I also suggest the following script of mine, to do the actual adjustments of the brightness. The script does it in exponential increments rather than linear, so it requires many less key presses to reach the desired luminosity:
USAGE="Usage: `basename $0` +|-|max|<number>"
if [ "$1" == "+" ]; then
bright=`echo "print(int(min($maxbright,$bright + max($bright * 0.5, 1))))" | python`
if [ "$1" == "-" ]; then
bright=`echo "print(int(max(0,$bright - max($bright * 0.33, 1))))" | python`
if [ "$1" == "max" ]; then
if ! [[ "$1" =~ ^[0-9]+$ ]] ; then
echo "`basename $0` version 0.1"
echo $USAGE >&2
echo "+|- brighter/darker"
echo "max maximum luminosity"
echo "<int> set specific light intensity"
echo $bright | tee $hwpath/brightness"
The Bash script needs a Python. Put it somewhere in the path (I name it
bright), and use it simply by
bright 50 (very dim screen, good for night work) or
If you want to use the script as a non-root user, please change the permissions for the
/sys/class/backlight/intel_backlight; the best place to do it is via the upstart job, since upstart jobs are executed by the root.
This script is compatible with at least 3 ASUS models: ASUS N56VZ, ASUS G551JM and ASUS P53E. I guess it should be compatible with most of the other ASSUSes out there, and after a minor modification, with all other notebook brands that expose screen brightness somewhere in the
/sys file system tree.