CARB replacement truck already throw codes.

2nd UPDATE:

Well, I ended up replacing both nox sensors, first the Inlet Nox (fault code 3216 fmi 20), and did a force regen, cleared the code. Truck was good for 2 weeks then fault code 3226 pop up. I kept clearing it and did a force regen and it would clear and pop back on a day or two later, it got to a point I would drive about 80 miles and it was there again after I would clear it. So I had the outlet Nox sensor replaced, forced a regen, code cleared. It’s been two week’s and everything good so far. Btw, I never had a derate while all this was going on. I also wanna say that the OTR tool does come in handy, but it’s just a patch job, the codes probably will come back sooner or later if there is a real issue. Thanks to @Goodysnap for the help.

 

It’s a temporary (wasted time fix)...... . All this emissions is new to me.