Theory Of Operation
WARNING: This page is about a different variant/trim than selected.
The Powertrain Control Module (PCM) monitors Diesel Exhaust Fluid (DEF) pressure and DEF Supply Pump lifts to determine frost build-up in the DEF Inlet and DEF Outlet lines. If the DEF Supply Pump lifts are too frequent and one of the DEF line pressure inputs is outside a calibrated threshold, the PCM will turn on the Malfunction Illumination Lamp (MIL) and set the DTC.