Injector, Diesel Exhaust Fluid: Operation
WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Diesel Exhaust Fluid (DEF) Injector is mounted to the decomposition tube at the inlet of the Selective Catalytic Reduction (SCR) Catalyst. The Powertrain Control Module (PCM) sends a Pulse Width Modulated (PWM) signal to the DEF Injector to vary the amount of fluid sprayed into the exhaust stream.