2020 Ram 3500 Chassis Cab maintenance

SAFETY151
Supplemental Restraint Systems (SRS)
Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on
others. If you are not sure, ask an authorized
dealer.
The air bag system must be ready to protect you
in a collision. The Occupant Restraint Controller
(ORC) monitors the internal circuits and inter -
connecting wiring associated with the electrical
Air Bag System Components. Your vehicle may
be equipped with the following Air Bag System
Components:
Air Bag System Components
Occupant Restraint Controller (ORC)
Air Bag Warning Light
Steering Wheel and Column
Instrument Panel
Knee Impact Bolsters
Driver and Front Passenger Air Bags
Seat Belt Buckle Switch
Supplemental Side Air Bags — If Equipped
Front and Side Impact Sensors — If Equipped
Seat Belt Pretensioners — If Equipped
Air Bag Warning Light
The ORC monitors the readiness of
the electronic parts of the air bag
system whenever the ignition switch
is in the START or ON/RUN position. If
the ignition switch is in the OFF position or in the
ACC position, the air bag system is not on and
the air bags will not inflate.
The ORC contains a backup power supply
system that may deploy the air bag system even
if the battery loses power or it becomes discon -
nected prior to deployment.
The ORC turns on the Air Bag Warning Light in
the instrument panel for approximately four to
eight seconds for a self-check when the ignition
switch is first in the ON/RUN position. After the
self-check, the Air Bag Warning Light will turn
off. If the ORC detects a malfunction in any part
of the system, it turns on the Air Bag Warning
Light, either momentarily or continuously. A
single chime will sound to alert you if the light
comes on again after initial startup. The ORC also includes diagnostics that will illu-
minate the instrument panel Air Bag Warning
Light if a malfunction is detected that could
affect the air bag system. The diagnostics also
record the nature of the malfunction. While the
air bag system is designed to be maintenance
free, if any of the following occurs, have an
authorized dealer service the air bag system
immediately.
The Air Bag Warning Light does not come on
during the four to eight seconds when the
ignition switch is first in the ON/RUN position.
The Air Bag Warning Light remains on after
the four to eight-second interval.
The Air Bag Warning Light comes on intermit
-
tently or remains on while driving.
NOTE:
If the speedometer, tachometer, or any engine
related gauges are not working, the Occupant
Restraint Controller (ORC) may also be
disabled. In this condition the air bags may not
be ready to inflate for your protection. Have an
authorized dealer service the air bag system
immediately.
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190STARTING AND OPERATING
3. While the "Wait to Start" telltale is on, the
instrument cluster will additionally display a
gauge or bar whose initial length represents
the full "Wait to Start" time period. Its length
will decrease until it disappears when the
"Wait to Start" time has elapsed.
4. After the engine “Wait to Start” telltale goes off, the engine will automatically crank. 5. After engine start-up, check to see that
there is oil pressure.
6. Release the parking brake and drive.
NOTE:
Engine idle speed will automatically increase
to 1,000 RPM and engage the Variable
Geometry Turbocharger at low coolant
temperatures to improve engine warm-up.
The engine will not automatically crank after
the engine "Wait to Start" telltale goes off if a
door or the hood is ajar.
If the engine stalls, or if the ignition switch is
left ON for more than two minutes after the
“Wait to Start” telltale goes out, reset the
intake air heater by turning the ignition
switch to the OFF position for at least 5
seconds and then back ON. Repeat steps 1
through 7 of “Keyless Enter-N-Go Starting
Procedure – Engine Manifold Air Tempera -
ture Below 66°F (19°C).”
Extreme Cold Weather
The Cummins Turbo Diesel engine is equipped
with several features designed to assist cold
weather starting and operation:
The engine block heater is a resistance
heater installed in the water jacket of the
engine just above and behind the oil filter. It
requires a 110–115 Volt AC electrical outlet
with a grounded, three-wire extension cord.
NOTE:
The engine block heater cord is a factory
installed option. If your vehicle is not equipped,
heater cords are available from your authorized
Mopar dealer.
A 12 Volt heater built into the fuel filter hous -
ings aid in preventing fuel gelling. It is
controlled by a built-in thermostat.
An intake air heater system both improves
engine starting and reduces the amount of
white smoke generated by a warming engine.
CAUTION!
If the “Water in Fuel Indicator Light” remains
on, DO NOT START the engine before you
drain the water from the fuel filters to avoid
engine damage. Refer to “Draining Fuel/
Water Separator Filter” in “Servicing And
Maintenance” for further information.
CAUTION!
Do not crank engine for more than 25
seconds at a time or starter motor damage
may result. Turn the ignition switch to the OFF
position and wait at least two minutes for the
starter to cool before repeating start
procedure.

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STARTING AND OPERATING191
Normal Starting Procedure — Engine
Manifold Air Temperature Above 66°F
(19°C)
Observe the instrument panel cluster lights
when starting the engine.

1. Always apply the parking brake.

2. Shift into PARK for an automatic transmis -
sion.
3. Place the ignition switch in the ON position and watch the instrument panel cluster
lights. 4. Place the ignition switch in the START posi
-
tion and crank the engine. Do not press the
accelerator during starting.
5. Check that the oil pressure warning light has turned off.
6. Release the parking brake.
Starting Procedure — Engine Manifold Air
Temperature 0°F To 66°F (–18°C to 19°C)
NOTE:
The temperature displayed in the instrument
cluster does not necessarily reflect the engine
manifold air temperature. Refer to “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel” for further information.
When engine temperatures fall below 66°F
(19°C) the “Wait To Start” telltale will remain on
indicating the intake air heater system is active.
Follow the steps in the “Normal Starting” proce -
dure except:

1. The “Wait to Start” telltale will remain on for a period of time that varies depending
on the engine temperature.

2. While the “Wait to Start” telltale is on, the instrument cluster will additionally display a
gauge or bar whose initial length represents
the full “Wait to Start” time period. Its length
will decrease until it disappears when the
“Wait to Start” time has elapsed.
CAUTION!
If the “Water in Fuel Indicator Light” remains
on, DO NOT START the engine before you
drain the water from the fuel filters to avoid
engine damage. Refer to “Draining Fuel/
Water Separator Filter” in “Servicing And
Maintenance” for further information.
CAUTION!
Do not crank engine for more than 25
seconds at a time or starter motor damage
may result. Turn the ignition switch to the OFF
position and wait at least two minutes for the
starter to cool before repeating start
procedure.
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192STARTING AND OPERATING
3. After the “Wait to Start” telltale goes off,
place the ignition switch in the START posi -
tion. Do not press the accelerator during
starting.
4. After engine start-up, check that the oil pressure warning light has turned off.
5. Release the parking brake and drive. NOTE:
Engine idle speed will automatically increase
to 1,000 RPM and engage the Variable
Geometry Turbocharger at low coolant
temperatures to improve engine warm-up.
Automatic equipped vehicles with optional
Keyless Enter-N-Go – If the ENGINE START/
STOP button is pushed once while in park
with the ignition off and driver’s foot on the
brake pedal, the vehicle will automatically
crank and start after the “Wait to Start” time
has elapsed. If it is desired to abort the start
process before it completes, the driver’s foot
should be fully removed from the brake pedal
prior to pushing the start button again in
order for the ignition to move directly to off.
If the engine stalls, or if the ignition switch is
left ON for more than two minutes after the
“Wait To Start” telltale goes out, reset the
intake air heater by turning the ignition
switch to the OFF position for at least five
seconds and then back ON. Repeat steps 1
through 5 of “Starting Procedure – Engine
Manifold Air Temperature Below 66°F
(19°C).”
Starting Procedure — Engine Manifold Air
Temperature Below 0°F (-18°C)
In extremely cold weather below 0°F (-18°C) it
may be beneficial to cycle the intake air heater
twice before attempting to start the engine. This
can be accomplished by turning the ignition OFF
for at least five seconds and then back ON after
the “Wait to Start” telltale has turned off, but
before the engine is started. However, exces
-
sive cycling of the intake air heater will result in
damage to the heater elements or reduced
battery voltage.
NOTE:
If multiple pre-heat cycles are used before
starting, additional engine run time may be
required to maintain battery state of charge at
a satisfactory level.
CAUTION!
If the “Water in Fuel Indicator Light” remains
on, DO NOT START the engine before you
drain the water from the fuel filters to avoid
engine damage. Refer to “Draining Fuel/
Water Separator Filter” in “Servicing And
Maintenance” for further information.
CAUTION!
Do not crank engine for more than 25
seconds at a time or starter motor damage
may result. Turn the ignition switch to the OFF
position and wait at least two minutes for the
starter to cool before repeating start
procedure.

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STARTING AND OPERATING193

1. If the engine stalls after the initial start, the
ignition must be turned to the OFF position
for at least five seconds and then to the ON
position to recycle the intake air heater.

NOTE:
Excessive white smoke and poor engine perfor -
mance will result if intake air heater are not
recycled.
2. Heat generated by the intake air heater dissipates rapidly in a cold engine. If more
than two minutes pass between the time
the “Wait to Start” telltale turns off and the
engine is started, recycle the intake air
heater by turning the ignition switch to the
OFF position for at least five seconds and
then back ON.
3. If the vehicle is driven and vehicle speed exceeds 19 mph (31 km/h) before the
intake air heater post-heat (after start) cycle
is complete, the intake air heater will shut
off.
4. If the engine is cranked for more than 10 seconds, the post-heat cycle will turn off. NOTE:
Engine idle speed will automatically increase
to 1,000 RPM and engage the Variable
Geometry Turbocharger at low coolant
temperatures to improve engine warm-up.
When a diesel engine is allowed to run out of
fuel or the fuel gels at low temperatures, air
is pulled into the fuel system. If your engine
has run out of fuel, refer to “Priming If The
Engine Has Run Out Of Fuel” in “Servicing
And Maintenance” for further information.
If the engine stalls, or if the ignition switch is
left ON for more than two minutes after the
“Wait to Start” telltale goes out, reset the
intake air heater by turning the ignition
switch to the OFF position for at least five
seconds and then back ON. Repeat steps 1
through 5 of “Starting Procedure – Engine
Manifold Air Temperature Below 66°F
(19°C).”
Starting Fluids
The engine is equipped with an automatic elec
-
tric air preheating system. If the instructions in
this manual are followed, the engine should
start in all conditions.
WARNING!
Starting fluids or flammable liquids must
never be used in the Cummins diesel engine
(see Warning label). Never pour diesel fuel,
flammable liquid, starting fluids (ether) into
the air cleaner canister, air intake piping, or
turbocharger inlet in an attempt to start the
vehicle. This could result in a flash fire and
explosion causing serious personal injury and
engine damage.
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196STARTING 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. Refer to “Fuel
Requirements” in “Technical Specifications”
for further information.
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 isnt 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
Refer to “Dealer Service” in “Servicing And
Maintenance” for the correct engine oil
viscosity.

Winter Front Cover Usage
A winter front or cold weather cover is to be used in
ambient temperatures below 32°F (0°C), espe
-
cially 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 tempera -
tures drop below 0°F (-17°C) the four flaps need
to be closed. A suitable cold weather cover is avail -
able from your 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.
Your vehicle is equipped with an engine warm
up protection feature that may limit engine
performance after cold starting at low ambient
temperatures. The length of time engine speed
is limited is dependent upon engine coolant
temperature. Engine speed may be briefly
limited to 1,000 RPM after starting with coolant
temperature below freezing conditions, and
may be limited to 1,000 RPM for up to approxi
-
mately 2 minutes under more severe cold
conditions.

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240STARTING AND OPERATING
Adaptive Cruise Control Set
When the RES (+) or the SET(-) button (located
on the steering wheel) is pushed, the display will
read “ACC SET.”
When ACC is set, the set speed will show in the
instrument cluster display.
The ACC screen may display once again if any
ACC activity occurs, which may include any of
the following:
System Cancel
Driver Override
System Off
ACC Proximity Warning
ACC Unavailable Warning
The instrument cluster display will return to
the last display selected after five seconds of
no ACC display activity
Display Warnings And Maintenance
“Wipe Front Radar Sensor In Front Of
Vehicle” Warning
The “ACC/FCW Unavailable Wipe Front Radar
Sensor” warning will display and also a chime
will indicate when conditions temporarily limit
system performance. This most often occurs at times of poor visibility,
such as in snow or heavy rain. The ACC system
may also become temporarily blinded due to
obstructions, such as mud, dirt or ice. In these
cases, the instrument cluster display will display
“ACC/FCW Unavailable Wipe Front Radar
Sensor” and the system will deactivate.
The “ACC/FCW Unavailable Wipe Front Radar
Sensor” message can sometimes be displayed
while driving in highly reflective areas (i.e.
tunnels with reflective tiles, or ice and snow).
The ACC system will recover after the vehicle
has left these areas. Under rare conditions,
when the radar is not tracking any vehicles or
objects in its path this warning may temporarily
occur.
NOTE:
If the “ACC/FCW Unavailable Wipe Front Radar
Sensor” warning is active Normal (Fixed Speed)
Cruise Control is still available. For additional
information refer to “Normal (Fixed Speed)
Cruise Control Mode” in this section.
If weather conditions are not a factor, the driver
should examine the sensor. It may require
cleaning or removal of an obstruction. The
sensor is located in the camera in the center of
the windshield, on the forward side of the rear
-
view mirror. To keep the ACC System operating properly, it is
important to note the following maintenance
items:
Always keep the sensor clean. Carefully clear
the windshield.
Do not remove any screws from the sensor.
Doing so could cause an ACC system
malfunction or failure and require a sensor
realignment.
Do not attach or install any accessories near
the sensor, including transparent material or
aftermarket grilles. Doing so could cause an
ACC system failure or malfunction.
When the condition that deactivated the system
is no longer present, the system will return to
the “Adaptive Cruise Control Off” state and will
resume function by simply reactivating it.
NOTE:
If the “ACC/FCW Unavailable Wipe Front
Radar Sensor” message occurs frequently
(e.g. more than once on every trip) without
any snow, rain, mud, or other obstruction,
have the radar sensor realigned at your
authorized dealer.

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STARTING AND OPERATING269
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.
Fuel Filler Cap
If the fuel filler cap is lost or damaged, be sure
the replacement cap is for use with this vehicle.
Avoid Using Contaminated Fuel
Fuel that is contaminated by water or dirt can
cause severe damage to the engine fuel
system. Proper maintenance of the engine fuel
filter and fuel tank is essential. Refer to “Dealer
Service” in “Servicing And Maintenance” for
further information.
Bulk Fuel Storage — Diesel Fuel
If you store quantities of fuel, good mainte -
nance of the stored fuel is also essential. Fuel
contaminated with water will promote the
growth of “microbes.” These microbes form
“slime” that will clog the fuel filtration system
and lines. Drain condensation from the supply
tank and change the line filter on a regular
basis.
NOTE:
When a diesel engine is allowed to run out of
fuel, air is pulled into the fuel system.
If the vehicle will not start, refer to “Priming If
The Engine Has Run Out Of Fuel” in “Servicing
And Maintenance” for further information.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.
WARNING!
Never have any smoking materials lit in or
near the vehicle when the fuel filler cap is
removed or the tank filled.
Never add fuel to the vehicle when the
engine is running.
CAUTION!
Damage to the fuel system or emission
control system could result from using an
improper fuel tank filler tube cap. A poorly
fitting cap could let impurities into the fuel
system.
WARNING!
Do not open the high pressure fuel system
with the engine running. Engine operation
causes high fuel pressure. High pressure fuel
spray can cause serious injury or death.
5

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