Set Condition:
WARNING: This page is about a different car, the 2011 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.
If during post fuel injection, the O2 Sensor 1/1 value is above a calibrated threshold a fail count is recorded as incremented. If not, it is recorded as decremented. After a calibrated number of total counts (incremented and decremented), the counter value is above a calibrated value, a fault is set.