Hi,
Please do try these troubleshooting steps that may help.
- Start by toggling the fn+F3 or fn+F4 and see if you'll see the backlight of the keyboard activate.
- If it will not work, uninstall/reinstall the ATK software.
- Open Device Manager first and uninstall the keyboard driver.
- Go to Programs and Features next then uninstall anything related to the ATK software for the keyboard.
- Reboot the laptop after uninstalling these software.
- After the reboot, download and install the ATK software again.
- Here's the link:
http/dlcdnet.asus.com/pub/ASUS/nb/Apps_for_Win8/ATKPackage/ATKPackage_Win8_64_Z100022.zip?_ga=1.53493674.305422646.1455979617
- Do test the keyboard again once everything has been installed.
- If it will still not work I would suggest opening the laptop to check if the ribbon cable is properly seated in the motherboard.
- If all these will not work please do replace the keyboard.