Assembly, Diesel Exhaust Fluid Pump: Operation: Operation
WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Diesel Exhaust Fluid (DEF) Supply Pump has many functions. It's primary purpose is to draw fluid from the tank and build adequate system pressure for dosing into the exhaust. The DEF Dosing Control Unit provides the 12 Volt supply and ground to the pump. The DEF Dosing Control Unit provides a Pulse Width Modulated (PWM) signal to the DEF Supply Pump to control the speed and output of the pump. The DEF Supply Pump has an internal temperature sensor which reports the internal temperature of the DEF Supply Pump to the DEF Dosing Control Unit.