Question

2011 Dodge 4500 6.7L with engine code P203F and P229F, can I reset all to clear codes?

Answer 1

P203F Diesel exhaust fluid low , reductant level too low

This is a important code that is set , when it set you also get a warning message on the instrument panel. If you run out of fluid and its truly empty the engine will not start. So yes if the fluid was low and the code was set because of the fluid go ahead and clear the code, or if the ECM see the correction it will clear within four ignition start up. proved there is no fault with the DEF dosing control unit

Answer 2

P203F DODGE Code - Reductant Level Sensor Circuit Too Low
Read more: https://www.autocodes.com/p203f_dodge.html

P229F DODGE Code - NOx Sensor Circuit Range/Performance Bank 2
Read more: https://www.autocodes.com/p229f_dodge.html