More than likely you have the same problem many 7 owners have - carboned-up heads, which prevent air from the air pump to circulate through them. It has NO EFFECT on how the vehicle performs, but it will fail emission testing. FWIW - repairing this will empty your wallet of approximately 7-12k dollars. Are you also getting P0492 codes? Usually you get both.
If you have a similar testing system as we do here in BC, you are allowed 1 readiness code not set and still pass testing. Sooooo.....if you reset your SES light and wait until the one last readiness monitor is not set (which will be the secondary air system), and then proceed with testing, you will pass.
If you have anymore questions, fire away. I have become somewhat of an expert on this problem, through extensive and painstaking research.