#change directory to where the LEDs are
cd /sys/class/leds/
ls 
#These are the LEDs available
ath9k-phy0        om2p:blue:lan     om2p:blue:power   om2p:blue:wan     om2p:green:wifi   om2p:red:wifi     om2p:yellow:wifi
#turn it off
echo "0" > om2p\:blue\:lan/brightness
#turn it on
echo "1" > om2p\:blue\:lan/brightness
#Go through all of them and confirm which is which on the device