When Monitored
WARNING: This page is about a different car, the 2014 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.
The PCM runs this monitor after every DEF refill event. There are several other criteria for monitoring this DTC including: ambient temperature exceeding -7.0°C (19.4°F), NOx Sensors are active, altitude is lower than 6,800 feet, and the vehicle has been driven at steady highway speeds for a sufficient amount of time.