The data is in the offline map downloaded by the head unit.
If you don't have a data plan, you don't get offline maps downloaded.
Assuming you have a data plan, it should happen automatically, but if you want to kick start it, connect the vehicle to WiFi (in your garage, to your cell hotspot, at Starbucks, whatever), Hit the Map, select the settings icon, select offline maps, download an offline map...
This will work for a few days if you don't have data...then the map will expire and try to re-download...if you have a data plan, you will be good, if not..back to where you are now.