When Monitored
WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Downstream O2 Sensor, located in the exhaust path behind the Catalytic Converter, is monitored for proper response to assure optimum Catalytic Converter efficiency. The Downstream O2 Sensor response monitor is intended to diagnose a Downstream O2 Sensor that is not moving or stuck in a voltage window and to insure accurate information for catalyst monitor diagnosis.
With the engine running, vehicle speed between 32 and 88 kph (20 and 55 mph), throttle open for a minimum of 120 seconds, ECT greater than 70°C (158°F), Catalytic Converter Temperature greater than 600°C (1112°F) and EVAP Purge active.