OK guys, I've been dealing with this code for awhile, SCR efficiency and NOx sensor codes.

Today I erased the code and went for a drive with coder reader displays NOx I and NOx II concentration.

NOx I displayed varies depends on speed and idle, but was reading around 40 to all the way 400 ppm.
Other hand NOx II was really dead sitting at -0.02 ppm and never changes.

I think my post NOx is dead what do you all think?

Thank you
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