You've cleared it and it still comes back?

Two things:

If it is the temp sensor in the SCR tank, the whole tank needs to be replaced. $1000 or so plus labor.

The tank is a COVERED COMPONENT under the California Emissions warranty, 7/70...however I dont think Kansas has adopted CA standards.

This came up recently somewhere else... if it were me, I'd inspect the tank, sensor, wiring....

A