Just need to activate it and it will notify you. I personally don’t use it however, I’m sure some people find it very useful. I am also sure many will criticize it and question its accuracy and viability. On these forums the latter is much more likely especially those who have never tried it. Current Garmin edge units have incredible of amount of features embedded into the system. Best to use Google and or YouTube to outline how to enable or disable each one if confused it’s extremely straightforward and all menu driven.