When Monitored

The PCM requires specific engine and after-treatment conditions to be met to run and complete this monitor. 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. NOx sensor data is gathered over varying engine speeds and loads. When enough data has been gathered, the diagnostic will run, make a pass/fail decision, and begin to gather data again.