Low DEF Warning Light went Red
Driving home thru NC mountains. 40 degree's and raining. cleared top mountain.
got warning horn, red DEF light. lost air pressure gauges, oil press. Pulled off next exit down hill. Added Def spare jug. Checked oil level, normal. called Freightliner. said most likely dirty plug by transmission passenger side. If levels OK, can drive to service center. Started to drive. Derated to 5 MPH. pulled over. Found connector. wet and dirty. didn't have contact cleaner. tried hair dryer to dry.no help. free AAA towing so went to service center. Spent night, arrived 2330. next day after 10am and sun all normal. Still had to have axle reinstalled with new paper gasket. $3.00. Tech reset codes. NTF. Now have a spare gasket in case of tow. Plug iced up due to rain plus temp and wind chill. next time will wait till sun warms up and see if corrected. Just a FYI in case this happens to some one else. Happy travels. New Class A owner. 2 months, 8K miles, 22 states. [Mod edit]