If you've been able to go 300 without any drivability issues, I would venture a guess you could keep driving it without incident, but just keeping an eye on any warnings that may pop up.Yeah, ive put about 300 miles on her since the light showed up, and it appears im not using any DEF at all. (25% and holding) Looks like im driving the truck until the part comes in.
Sounds like you are in the military, Air Force? The average person doesn't know what a cannon plug is.P21DD in history. Code is gone. No idea why. Multiple restarts and some spirited driving.... i didnt clear it. (Maybe a loose connection at a cannon plug?) Im sure it will come back though.