derate 3712, 3714, 2976

[montrose818]

Hello, 2015 ISL9 here.

Changed out my NOX and doser unit (genuine cummin) to get rid of some codes and it did, but left with these three now. Ran a regen, completed, codes still there. Ran an SCR test, eventually truck shuts off, Aftertreatment Warm Up an DEF dosing test says stopped, check status window, but status window just says Running.

Ive been reading and some suggest updating the ECU, or maybe the doser pump for the 2976 code.

Flashing this truck is unfortunately not an option, as it needs to be passing the biannual CA smog check.

Thanks for your help.