2020 n-series w/5.2 diesel came in with code for to much water in def. Pulled tank cleaned and put in new fluid. This is a chevy badged truck so IDSS will not connect. Used Gm program to connect , all codes cleared none came back. Dash lights for scr and d-rate still on. Still goes to d-rate when started still no codes. Used Gm program to update pcm Scr modals. Still no change . I can bring up shop manuals in Idss for this truck ,but the way they say to clear does not work . Any thoughts on what i may have missed. Thanks for any help.

Robert Divers
Owner/Technician
Techne Mechanical
Roanoke, Virginia, USA