Ram Trucks 2015 Chassis Cab Commercial - Diesel Supplement - Manual (Page 272)

The purpose of the SCR system is to reduce levels of NOx
(oxides of nitrogen emitted from engines) that are harm-
ful to our health and the environment to a near-zero level.
Small quantities of Diesel Exhaust Fluid (DEF) is injected
into the exhaust upstream of a catalyst where, when
vaporized, it converts smog-forming nitrogen oxides
(NOx) into harmless nitrogen (N2) and water vapor
(H2O), two natural components of the air we breathe.
You can operate with the comfort that your vehicle is
contributing to a cleaner, healthier world environment
for this and generations to come.
System Overview
This vehicle is equipped with a Diesel Exhaust Fluid
(DEF) injection system and a Selective Catalytic Reduc-
tion (SCR) catalyst to meet the emission requirements.
The DEF injection system consists of the following com-
ponents:
• DEF tank
• DEF pump
• DEF injector
• Electronically-heated DEF lines
• DEF control module
• NOx sensors
• NH3 sensor
• Temperature sensors
• SCR catalyst
270 STARTING AND OPERATING