It looks like this is generally a setting available in your BIOS. Perhaps [https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/yoga-series/yoga-2-pro-lenovo/solutions/HT100118|this] will help. You could also go [http://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/yoga-series/yoga-2-pro-lenovo/solutions?searchLocation=PSPSol_S|here] and search for ''fn key'' or something similar.