2005 chevy trailblazer check engine code


I am getting a code p0410 and its a secondary air injection. I know the pump runs not sure if the valve is working. I read on the net that it could be the 02 sensor. I want to make sure before I buy the valve. Has any body had this problem?
The valves seize up,if you have air coming out of the pump(like a mini turbo:D ) it's good,99% the valve is bad. I work a the dealer and have seen it plenty.