I have a 2008 HHR 2LT that I just bought used about a week ago (10K miles)!
What build code would I look for to see if my car has satellite radio? It has the second antenna on the roof near the back but nothing that tells me it's satellite. I hit the "band" button on the radio and nothing comes up there about XM or Sirius.

 

probably onstar ant....if it doesnt show on radio then no...xm has a teaser station if its there..

 

If you had it - you would know.

XM shows up on the radio even if you don't pay.
You just get ads playing and a "please subscribe" message on the screen.