secondary air pump and solenoid location on 2007 Chevrolet Impala

Have code Po411,3.5 07 impala,incorrect air flow,where is pump located,and also the pump solenoid location,also fuse locations for the above mentioned items.

Asked by for the 2007 Chevrolet Impala
you may just have a bad ck valve ck that 1st
Thnx,can u pin -point the location of the CK valve,and is their more than one on this car.
at the end of both exh pipe rails on top of the exh manifolds
what is the ck valve please?