2021 RAM CHASSIS CAB fuel pump

82GETTING TO KNOW YOUR INSTRUMENT PANEL
6. Temperature Gauge
The gauge pointer shows engine coolant
temperature. The pointer positioned
within the normal range indicates that
the engine cooling system is operating
satisfactorily.
The gauge pointer will likely indicate a
higher temperature when driving in hot
weather, up mountain grades, or when
towing a trailer. It should not be allowed
to exceed the upper limits of the normal
operating range. 7. Fuel Gauge
The pointer shows the level of fuel in
the fuel tank when the ignition is in the
ON/RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel door is located.
WARNING!

A hot engine cooling system is dangerous.
You or others could be badly burned by steam
or boiling coolant. It is recommended to call an
authorized dealer for service if your vehicle
overheats. If you decide to look under the hood
yourself, Follow the warnings under the Cooling
System Pressure Cap paragraph
Ú
page 383.

CAUTION!

Driving with a hot engine cooling system could
damage your vehicle. If the temperature gauge
reads “H,” pull over and stop the vehicle. Idle
the vehicle with the air conditioner turned off
until the pointer drops back into the normal
range. If the pointer remains on the “H,” turn
the engine off immediately and call an
authorized dealer for service.

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84GETTING TO KNOW YOUR INSTRUMENT PANEL
PREMIUM INSTRUMENT CLUSTER
D
ESCRIPTIONS

1. Tachometer

Indicates the engine speed in revolutions
per minute (RPM x 1000).
2. Instrument Cluster Display
When the appropriate conditions exist,
this display shows the instrument cluster
display messages Ú page 90.

Premium Instrument Cluster Display

The display always shows one of the main
menu item after ignition on. 3. Speedometer
Indicates vehicle speed.
4. Temperature Gauge
The gauge pointer shows engine coolant
temperature. The pointer positioned
within the normal range indicates that
the engine cooling system is operating
satisfactorily.
The gauge pointer will likely indicate a
higher temperature when driving in hot
weather, up mountain grades, or when
towing a trailer. It should not be allowed
to exceed the upper limits of the normal
operating range. 5. Fuel Gauge
The pointer shows the level of fuel in
the fuel tank when the ignition is in the
ON/RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel door is located.
1 – Instrument Cluster Display Controls
2 – Instrument Cluster Display Screen
WARNING!

A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. It is recommended to call an authorized
dealer for service if your vehicle overheats. If you
decide to look under the hood yourself, Follow the
warnings under the Cooling System Pressure Cap
paragraph
Ú
page 383.

CAUTION!

Driving with a hot engine cooling system could
damage your vehicle. If the temperature gauge
reads “H,” pull over and stop the vehicle. Idle the
vehicle with the air conditioner turned off until the
pointer drops back into the normal range. If the
pointer remains on the “H,” turn the engine off
immediately and call an authorized dealer for
service.

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GETTING TO KNOW YOUR INSTRUMENT PANEL87
4. Oil Pressure Gauge
The pointer should always indicate some
oil pressure when the engine is running.
A continuous high or low reading under
normal driving conditions may indicate a
lubrication system malfunction. Imme-
diate service should be obtained from an
authorized dealer.
5. Speedometer
Indicates vehicle speed. 6. Diesel Exhaust Fluid (DEF) Gauge

The DEF Gauge displays the actual level of
Diesel Exhaust Fluid in the DEF tank. DEF
is required to maintain normal vehicle
operation and emissions compliance. If
something is wrong with the gauge, a DEF
Warning Message or Malfunction Indicator
Light (MIL) will be displayed. More informa
-
tion is available in the instrument cluster
display section under the heading of DEF
Warning Messages.

7. Fuel Gauge
The pointer shows the level of fuel in the
fuel tank when the ignition switch is in
the ON/RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel filler door is located. NOTE:
The gauge may take up to five seconds to
update after adding a gallon or more of DEF
to the DEF tank. If you have a fault related to
the DEF system, the gauge may not update to
the new level. See an authorized dealer for
service.
The DEF gauge may also not immediately
update after a refill if the temperature of the
DEF fluid is below 39°F (4°C). The DEF tank
heater will possibly warm up the DEF fluid
and allow the gauge to update after a period
of run time. Under very cold conditions, it is
possible that the gauge may not reflect the
new fill level for several drives.
3

21_DPF_OM_EN_USC_t.book Page 87

GETTING TO KNOW YOUR INSTRUMENT PANEL89
DIESEL INSTRUMENT CLUSTER

1. Tachometer

Indicates the engine speed in revolutions
per minute (RPM x 1000).
2. Instrument Cluster Display
When the appropriate conditions exist,
this display shows the instrument cluster
display messages Ú page 90.

Premium Instrument Cluster Display

The display always shows one of the main
menu item after ignition on. 3. Speedometer
Indicates vehicle speed.
4. Diesel Exhaust Fluid (DEF) Gauge
The DEF Gauge displays the actual level
of Diesel Exhaust Fluid in the DEF tank.
DEF is required to maintain normal
vehicle operation and emissions compli -
ance. If something is wrong with the
gauge, a DEF Warning Message or
Malfunction Indicator Light (MIL) will be
displayed. More information is available
in the instrument cluster display section
under the heading of Diesel Exhaust
Fluid (DEF) Warning Messages.
5. Fuel Gauge
The pointer shows the level of fuel in the
fuel tank when the ignition switch is in
the ON/RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel filler door is located. NOTE:
The DEF tank on these vehicles is designed
with a large amount of full reserve. So the
level sensor will indicate a full reading even
before the tank is completely full. To put it
another way, there’s additional storage
capacity in the tank above the Full mark
that’s not represented in the gauge. You may
not see any movement in the reading – even
after driving up to 200 miles (321 kilome
-
ters) in some cases.
The gauge may take up to five seconds to
update after adding a gallon or more of DEF
to the DEF tank. If you have a fault related to
the DEF system, the gauge may not update to
the new level. See an authorized dealer for
service.
The DEF gauge may also not immediately
update after a refill if the temperature of the
DEF fluid is below 39°F (4°C). The DEF tank
heater will possibly warm up the DEF fluid
and allow the gauge to update after a period
of run time. Under very cold conditions, it is
possible that the gauge may not reflect the
new fill level for several drives.
1 – Instrument Cluster Display Controls
2 – Instrument Cluster Display Screen
3

21_DPF_OM_EN_USC_t.book Page 89

130STARTING AND OPERATING
NOTE:
Use of Climatized ULSD or Number 1 ULSD
Fuel results in a noticeable decrease in fuel
economy.

Climatized ULSD Fuel is a blend of Number 2
ULSD and Number 1 ULSD Fuels which
reduces the temperature at which wax crystals
form in fuel.

The fuel grade should be clearly marked on
the pump at the fuel station.
The engine requires the use of “ULSD Fuel”.
Use of incorrect fuel could result in engine
and exhaust system damage Ú page 433.
If climatized or diesel Number 1 ULSD Fuel is
not available, and you are operating below
(20°F/-6°C), in sustained arctic conditions,
Mopar Premium Diesel Fuel Treatment
(or equivalent) is recommended to avoid
gelling (see Fuel Operating Range Chart).
Under some circumstances increased engine
noise may be audible in the seconds
following a cold start. This is most likely to
occur when using fuel that isn't blended for
the ambient temperature present. This may
occur on an unseasonably cold day or when a truck is fueled in a warmer climate and driven
to a colder climate. The noise can typically be
prevented by using Mopar Premium Diesel
Fuel Treatment as recommended (see Fuel
Operating Range Chart).
Engine Oil Usage
For the correct engine oil viscosity
Úpage 367.
Winter Front Cover Usage

A Winter front or cold weather cover is to be used
in ambient temperatures below 32°F (0°C),
especially during extended idle conditions.
This cover is equipped with four flaps for
managing total grille opening in varying ambient
temperatures. If a Winter front or cold weather
cover is to be used the flaps should be left in
the full open position to allow air flow to the
charge air cooler and automatic transmission
oil cooler. When ambient temperatures drop
below 0°F (-17°C) the four flaps need to be
closed. A suitable cold weather cover is available
from a Mopar dealer.

Battery Blanket Usage
A battery loses 60% of its cranking power as the
battery temperature decreases to 0°F (-18°C).
For the same decrease in temperature, the
engine requires twice as much power to crank
at the same RPM. The use of 120 Volts AC
powered battery blankets will greatly increase
starting capability at low temperatures. Suitable
battery blankets are available from an
authorized Mopar dealer.
Engine Warm-Up
Avoid full throttle operation when the engine is
cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow the
oil pressure to stabilize as the engine warms up.
NOTE:
High-speed, no-load running of a cold engine
can result in excessive white smoke and poor
engine performance. No-load engine speeds
should be kept under 1,000 RPM during the
warm-up period, especially in cold ambient
temperature conditions.

21_DPF_OM_EN_USC_t.book Page 130

132STARTING AND OPERATING
Idle-Up Feature

The driver-controlled high idle speed feature will
help increase cylinder temperatures and provide
additional cab heat, however, excessive idling may
still cause the exhaust after-treatment system to not
properly regenerate. Extended periods of idle time
should be avoided.

The Idle-Up feature uses the Cruise Control
buttons to increase engine idle speed and
quickly warm the vehicle's interior.

1. With the transmission in PARK, the parking
brake applied, and the engine running,
turn on the Cruise Control, then push the
SET (-) button.

2. The engine RPM will go up to 1,100 RPM. To increase the RPM, push and hold the
RES (+) button and the idle speed will
increase to approximately 1,500 RPM.
To decrease the RPM, push and hold the
SET (-) button and the idle speed will
decrease to approximately 1,100 RPM. 3. To cancel the Idle–Up feature, either push
the CANCEL button, push the ON/OFF
button, or press the brake pedal.
NOISE
Diesel engines can create noises that may
seem as a concern. The nature of a diesel
engine is compression ignition where
compressed air and fuel are mixed and ignited.
Weather, barometric pressure, altitude and
temperature will affect how fuel is ignited in the
engine. Engines will sound different from day to
day or previous model years. Clicking, ticking, or
light knocking is normal and will change from
day to day, as the engine breaks in, and can
vary with changes in ambient temperature; this
is normal. Diesel equipped vehicles also have
an exhaust after treatment system to reduce
emissions utilizing a Diesel Particulate Filter
(DPF) and a Selective Reduction Catalyst (SCR). The SCR reduces Nox using the Diesel Exhaust
Fluid (DEF) system. DEF is injected directly into
the SCR through an dosing module. This
process will create a clicking sound and at
times, will make noise even with the vehicle
shut off. This is normal as the DEF dosing
module is purging DEF. Fuel pump noise may
increase during low speed/light load conditions
when ambient temperature is above 100°F
(38°C), and when fuel tank level is below 10%.
This is a normal condition of the fuel system and
controls strategy. If at any time the check
engine light is on, please visit an authorized
dealer.

21_DPF_OM_EN_USC_t.book Page 132

STARTING AND OPERATING195
ENGINE RUNAWAY
Diesel engine runaway is a rare condition
affecting diesel engines, where the engine
consumes its own lubrication oil and runs at
higher and higher RPM until it overspeeds to
a point where it destroys itself due to either
mechanical failure or engine seizure through
lack of lubrication.
REFUELING THE VEHICLE — GASOLINE
ENGINE
NOTE:
When the fuel nozzle “clicks” or shuts off the
fuel tank is full. NOTE:
Tighten the gas cap a quarter turn until you hear
one click. This is an indication that the cap is
properly tightened.
If the gas cap is not tightened properly, the
Malfunction Indicator Light will come on.
Be sure the gas cap is tightened every time the
vehicle is refueled.
WARNING!
In case of engine runaway due to flammable
fumes from fuel spills or turbocharger oil
leaks being sucked into the engine, do the
following to help avoid personal injury and/or
vehicle damage:
Turn the ignition switch to the OFF position.

Using a CO2 or dry chemical type fire extin
-
guisher, direct the spray from the fire extin -
guisher into the grille on the passenger side so
that the spray enters the engine air intake.

The inlet for the engine air intake is located
behind the passenger side headlamp and
receives air through the grille.
CAUTION!
Damage to the fuel system or emissions
control system could result from using an
improper fuel tank filler tube cap (fuel filler
cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly-fitted
aftermarket cap can cause the MIL
(Malfunction Indicator Light) to illuminate
due to fuel vapors escaping from the
system.
A poorly fitting fuel filler cap may cause the
MIL to turn on.
To avoid fuel spillage and overfilling, do not
“top off” the fuel tank after filling.
WARNING!
Never have any smoking materials lit in
or near the vehicle when the gas cap is
removed or the tank is being filled.
Never add fuel to the vehicle when the
engine is running. This is in violation of
most state and federal fire regulations and
may cause the MIL to turn on.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle.
You could be burned. Always place gas
containers on the ground while filling.
4

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196STARTING AND OPERATING
LOOSE FUEL FILLER CAP MESSAGE
If the vehicle diagnostic system
determines that the fuel filler cap
is loose, improperly installed, or
damaged, a loose gASCAP indicator
will display in the instrument cluster telltale
display area Ú page 90. Tighten the fuel filler
cap properly and push the RIGHT button to turn
off the message. If the problem continues, the
message will appear the next time the vehicle is
started.
REFUELING THE VEHICLE — DIESEL ENGINE
NOTE:
When the fuel nozzle “clicks” or shuts off, the
fuel tank is full.
Tighten the fuel filler cap until you hear a
“clicking” sound. This is an indication that the
fuel filler cap is properly tightened.
Make sure that the fuel filler cap is tightened
each time the vehicle is refueled.
DIESEL EXHAUST FLUID
Your vehicle is equipped with a Selective
Catalytic 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 quantity
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
For system messages and warnings Úpage 90.
CAUTION!
To avoid fuel spillage and overfilling, do not
“top off” the fuel tank after filling.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle.
You could be burned. Always place gas
containers on the ground while filling.

21_DPF_OM_EN_USC_t.book Page 196