No, the dealer should've activated that on the day of the sale of your car. If it's still not active - you can try re-activating it using this site: http://www.siriusxm.com/oemrefresh or call the dealer to do it.
After letting my free subscription lapse, I resubscribed to the traffic service but it never went active on my head unit, even after sending a refresh signal. Ended up having to spend 15 minutes on the phone with them to get that resolved. Just FYI.
No argument that Waze is a much better service, but in some parts of the country at least (NY metro, in my case), I find SiriusXM's traffic to be quite usable (and the 1 year promo rate is less than $2 a month). Since I can't mirror my screen on the 2015's head unit, I much prefer the clean nav integration to mounting a phone. Of course, I always have my phone handy when comprehensive traffic-avoidance is critical - SiriusXM's service mostly covers major roads and highways, and can't update nearly as fast.