p2215-nox sensor circuit low input bank2
 

hello
my w203 c-220 cdi disel 2004 143 hp got fault code:
p2215-nox sensor circuit low input bank2

is this the lambda sensor?

which one of them is fault? cause there are 2 sensor
one is located in the entrance catalytic cinverter and the other is in the out.

change both of them?

thanks!!