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STARTING AND OPERATING
Diesel Exhaust Fluid
Your vehicle is equipped with a Selective Cata
-
lytic Reduction (SCR) system to meet the very
stringent diesel emissions standards required
by the Environmental Protection Agency.
The purpose of the SCR system is to reduce
levels of NOx (oxides of nitrogen emitted from
engines) that are harmful to our health and the
environment to a near-zero level. A small quan
-
tity 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 Reduction (SCR) catalyst to meet the
emission requirements.
The DEF injection system consists of the
following components:
DEF tank
DEF pump
DEF injector
Electronically-heated DEF lines
DEF control module
NOx sensors
Temperature sensors
SCR catalyst
UQS Sensor
Refer to “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel” for
system messages and warnings.
NOTE:
Your vehicle is equipped with a DEF injection
system. You may occasionally hear an
audible clicking noise. This is normal opera
-
tion.
The DEF pump will run for a period of time
after engine shutdown to purge the DEF
system. This is normal operation.
Diesel Exhaust Fluid Storage
Diesel Exhaust Fluid (DEF) is considered a very
stable product with a long shelf life. If DEF is
kept in temperatures between 10° and 90°F
(-12° and 32°C), it will last a minimum of one
year.
DEF is subject to freezing at the lowest tempera
-
tures. For example, DEF may freeze at tempera
-
tures at or below 12°F (-11°C). The system has
been designed to operate in this environment.
NOTE:
When working with DEF, it is important to know
that:
Any containers or parts that come into
contact with DEF must be DEF compatible
(plastic or stainless steel). Copper, brass,
aluminum, iron or non-stainless steel should
be avoided as they are subject to corrosion
by DEF.
If DEF is spilled, it should be wiped up
completely.
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