Set Condition:
WARNING: This page is about a different car, the 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) will set this fault if it detects that the DOC/DPF Catalyst closed loop control fueling adjustment has reached it's maximum allowable fueling but is unable to reach the target regeneration temperature.