I just went through this. What a nightmare. Situation - bought '12 TDI in Sept '11, told it had a 3 mo trial and to call Sirius when trial ended. No problem. Service actually didn't shut off until this Tuesday, so basically got a year free

Sirius and Traffic worked fine up until then. Called Sirius and they told me that because I bought a new VW I qualified for a free 3 month trial (I wasn't gonna argue the point), and I asked that they turned the traffic on as well. That's where the problem started. Since the 850 apparently only has one ESN (Same Radio ID for both Sirius radio and traffic), Sirius says that the radio doesn't get traffic. After arguing with 3 or 4 different reps who all insisted that traffic won't work because there is only 1 ESN, I called VW Touareg Exec Service who told me they will get with Sirius and correct the issue, and call me in a few days. I had my radio service back but no traffic. Then yesterday, traffic magically started working again. Honestly, I don't think it's because VW got anything accomplished, but because Sirius is running a free trial for traffic from 8/29-9/13
SiriusXM Traffic Overview - SiriusXM Radio My guess is that they turned traffic on for all customers whether their radio supports it or not, and since ours does, it works, even though the Cust Service Reps don't agree. Guessing on the 14th it will shut off again, unless VW Exec team gets the issue fixed at Sirius.
Try your traffic today and see if you get it due to the free 2 week trial.