The GPS is the hardware chip inside the phone that communicates with the satellites. Maps is the app that uses the signal the GPS chip receives. The GPS itself doesn't use data for it's communication since it's satellite (other than a little as mentioned). So if you're asking if GPS uses data, no. If you're asking if the Maps app uses data, yes, a fair amount.
There are other things that use the GPS, like speedometers or gps testing tools that use no data, so it's not the GPS that uses data, it's the apps that may need to download map images.