Sensor, Diesel Exhaust Fluid, Pressure: Operation: Operation
WARNING: This page is about a different car, the 2014 RAM 3500 HD and 2014 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Diesel Exhaust Fluid (DEF) Pressure Sensor is a three wire sensor, housed inside the DEF Supply Pump that monitors supplied pressure to the DEF Injector. The DEF Dosing Control Unit provides a 5-Volt supply and ground to the DEF Pressure Sensor. The sensor provides a signal to the DEF Dosing Control Unit on the DEF Pressure Sensor Signal circuit. This DEF Pressure Sensor Signal voltage changes, based on the diesel exhaust fluid pressure supplied by the DEF Supply Pump. The DEF Dosing Control Unit uses this information to vary pump speed and maintain the 130 psi (9 bar) pressure needed for proper DEF Injection.