I have an problem when it first starts in the morning it starts great but goes into (fail safe mode) derated mode until normal temp then it runs normal. It has been doing this for 3 months now. I replaced the IAT sensor but didn’t help but seem to run better when it warms up. I am looking for suggestions of what to check next?

 

Engine Coolant Temp sensor. From reading on here, Dodge doesn't know the engine has one of these, so Cummins would be the place to get one.

 

Sounds like what I was looking for, the gauge works fine, would you have any idea where it might be located?

 

I believe its by the thermostat, left front corner of the head.