Exhaust Fluid System Fault

My 2016 CC F350 DRW showed a message Saturday that speed would be limited to 50MPH in 50miles. I acknowledged the message and received an Exhaust Fluid System Fault. Went to Autozone and no DTC codes are showing. The DEF level shows as OK when I do a system check. I’m still under the power train warranty sobI don’t want to do a ******. Does anyone have any suggestions. I have an appointment at the dealer on Thursday.

Tom, we've seen some come in with bad DEF sensors. I also was wary of dieting before my warranty was up, but parts fell off of mine at 46k now I'm at 111k and it hasn't skipped a beat. Let us know what they say!

On the way to the dealer on Wednesday the fault cleared itself. Today they tested it and were not able to determine the fault. There were no codes in the system.

That's good news!