Theory Of Operation
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 Powertrain Control Module (PCM) monitors two separate systems for this DTC: The Variable Geometry Turbocharger (VGT) Actuator and the Diesel Exhaust Fluid (DEF) Dosing Control Module. This DTC specifically monitors the 12-Volt Supply circuits for each of these devices. If this DTC is active, the Diagnostic Tree will flow toward testing VGT circuits. If this DTC is not active, the Diagnostic tree will flow toward testing DEF Dosing Control Module (Heater) circuits.