When Monitored
WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
This monitor will be triggered 300 seconds after ignition-on or refill. Also, the DEF fluid temperature measured by both the DEF Quality/Temperature Sensor and the DEF Level/Temperature Sensor must be above 3°C (37°F). The Diagnostic is delayed at a temperature below 10°C (50°F) for 30 minutes before running and will be paused if the vehicle speed drops below 4.8 km/hr (3.0 mph) for 240 seconds.