2020 Ram 3500 Chassis Cab coolant

110GETTING TO KNOW YOUR INSTRUMENT PANEL
Vehicle Security Warning Light — If Equipped
This light will flash at a fast rate for
approximately 15 seconds when the
vehicle security alarm is arming, and
then will flash slowly until the vehicle
is disarmed.
Engine Coolant Temperature Warning Light
This warning light warns of an over -
heated engine condition. If the engine
coolant temperature is too high, this
indicator will illuminate and a single
chime will sound. If the temperature reaches
the upper limit, a continuous chime will sound
for four minutes or until the engine is able to
cool, whichever comes first.
If the light turns on while driving, safely pull over
and stop the vehicle. If the A/C system is on,
turn it off. Also, shift the transmission into
NEUTRAL and idle the vehicle. If the tempera -
ture reading does not return to normal, turn the
engine off immediately and call for service.
Refer to “If Your Engine Overheats” in “In Case
Of Emergency” for further information.
Battery Charge Warning Light
This warning light will illuminate when
the battery is not charging properly. If
it stays on while the engine is running,
there may be a malfunction with the
charging system. Contact an authorized dealer
as soon as possible.
This indicates a possible problem with the elec -
trical system or a related component.
Oil Pressure Warning Light
This warning light will illuminate to
indicate low engine oil pressure. If the
light turns on while driving, stop the
vehicle, shut off the engine as soon as
possible, and contact an authorized dealer. A
chime will sound when this light turns on.
Do not operate the vehicle until the cause is
corrected. This light does not indicate how
much oil is in the engine. The engine oil level
must be checked under the hood.
Oil Temperature Warning Light
This warning light will illuminate to
indicate the engine oil temperature is
high. If the light turns on while driving,
stop the vehicle and shut off the
engine as soon as possible. Wait for oil
temperature to return to normal levels.
Electronic Throttle Control (ETC) Warning
Light
This warning light will illuminate to
indicate a problem with the Electronic
Throttle Control (ETC) system. If a
problem is detected while the vehicle
is running, the light will either stay on or flash
depending on the nature of the problem. Cycle
the ignition when the vehicle is safely and
completely stopped and the transmission is
placed in the PARK position. The light should
turn off. If the light remains on with the vehicle
running, your vehicle will usually be drivable;
however, see an authorized dealer for service
as soon as possible.
NOTE:
This light may turn on if the accelerator and
brake pedals are pressed at the same time.

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GETTING TO KNOW YOUR INSTRUMENT PANEL113
Low Washer Fluid Warning Light — If
Equipped
This warning light will illuminate when
the windshield washer fluid is low.
Refer to “Engine Compartment” in “Servicing
And Maintenance” for further information.
Low Fuel Warning Light
When the fuel level reaches approxi -
mately 3.2 gal (12 L) this light will turn
on, and remain on until fuel is added.
A single warning chime will sound with Low Fuel
Warning.
Low Coolant Level Warning Light
This telltale will turn on to indicate the
vehicle coolant level is low.
Refer to “Dealer Service” in “Servicing And
Maintenance” for further information.
Loose Fuel Filler Cap Warning Light — If
Equipped
This warning light will illuminate when
the fuel filler cap is loose. Properly
close the filler cap to disengage the light. If the light does not turn off, please see an
authorized dealer.
Tire Pressure Monitoring System (TPMS)
Warning Light — If Equipped
The warning light switches on and a
message is displayed to indicate that
the tire pressure is lower than the
recommended value and/or that slow
pressure loss is occurring. In these cases,
optimal tire duration and fuel consumption may
not be guaranteed.
Should one or more tires be in the condition
mentioned above, the display will show the indi -
cations corresponding to each tire.
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. If your
vehicle has tires of a different size than the size
indicated on the vehicle placard or tire inflation
pressure label, you should determine the
proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a Tire Pressure Monitoring
System (TPMS) that illuminates a low tire pres
-
sure telltale when one or more of your tires is
significantly under-inflated. Accordingly, when
the low tire pressure telltale illuminates, you
should stop and check your tires as soon as
possible, and inflate them to the proper pres -
sure. Driving on a significantly under-inflated
tire causes the tire to overheat and can lead to
tire failure. Under-inflation also reduces fuel
efficiency and tire tread life, and may affect the
vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure,
even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire pres -
sure telltale.
CAUTION!
Do not continue driving with one or more flat
tires as handling may be compromised. Stop
the vehicle, avoiding sharp braking and
steering. If a tire puncture occurs, repair
immediately using the dedicated tire repair
kit and contact an authorized dealer as soon
as possible.
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182SAFETY
Periodic Safety Checks You Should Make
Outside The Vehicle
Tires
Examine tires for excessive tread wear and
uneven wear patterns. Check for stones, nails,
glass, or other objects lodged in the tread or
sidewall. Inspect the tread for cuts and cracks.
Inspect sidewalls for cuts, cracks, and bulges.
Check the wheel bolts for tightness. Check the
tires (including spare) for proper cold inflation
pressure.
Lights
Have someone observe the operation of brake
lights and exterior lights while you work the
controls. Check turn signal and high beam indi -
cator lights on the instrument panel.
Door Latches
Check for proper closing, latching, and locking.
Fluid Leaks
Check area under the vehicle after overnight
parking for fuel, coolant, oil, or other fluid leaks.
Also, if gasoline fumes are detected or if fuel, or
brake fluid leaks are suspected, the cause
should be located and corrected immediately.
ALWAYS make sure objects cannot fall or
slide into the driver’s side floor area when
the vehicle is moving. Objects can become
trapped under accelerator, brake, or clutch
pedals and could cause a loss of vehicle
control.
NEVER place any objects under the floor
mat (e.g., towels, keys, etc.). These objects
could change the position of the floor mat
and may cause interference with the accel -
erator, brake, or clutch pedals.
If the vehicle carpet has been removed and
re-installed, always properly attach carpet
to the floor and check the floor mat
fasteners are secure to the vehicle carpet.
Fully depress each pedal to check for inter -
ference with the accelerator, brake, or
clutch pedals then re-install the floor mats.
It is recommended to only use mild soap
and water to clean your floor mats. After
cleaning, always check your floor mat has
been properly installed and is secured to
your vehicle using the floor mat fasteners
by lightly pulling mat.
WARNING! (Continued)

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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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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.
5

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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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STARTING AND OPERATING197
NOTE:
If ambient temperatures are low and the
coolant temperature is below 180°F (82°C),
the engine idle speed will slowly increase to
1,000 RPM after two minutes of idle, if the
following conditions are met:
Foot is off brake pedal and throttle pedal.
Automatic transmission is in PARK.
Vehicle speed is 0 mph (0 km/h).
Applying the throttle will cancel fast idle.
Operating the exhaust brake at idle will
greatly improve warm up rate and will help
keep the engine close to operating tempera -
ture during extended idle.
Engine Idling
Avoid prolonged idling, long periods of idling
may be harmful to your engine because
combustion chamber temperatures can drop so
low that the fuel may not burn completely.
Incomplete combustion allows carbon and
varnish to form on piston rings, engine valves,
and injector nozzles. Also, the unburned fuel
can enter the crankcase, diluting the oil and
causing rapid wear to the engine.
If the engine is allowed to idle or the truck is
driven on low engine speed drive cycles for
more than 2 hours, the system will automati -
cally enter an emissions operating mode that
will increase the engine idle speed to 900 RPM
(1,050 RPM for Chassis Cab). While in this
mode, which is designed to help maintain the
Diesel Particulate Filter, the engine idle speed
will return to normal when the brake pedal is
applied. A small change in engine tone or a
slight change in engine performance while
accelerating may also be noticeable at speeds
below 20 mph (32 kmh). This operating mode
may last for up to an hour of idle time, or around
20 minutes of driving time. Your truck may have been ordered with an
optional voltage monitoring idle up feature. If a
load is placed on the electrical system while the
truck is in park, this feature will attempt to
maintain normal system voltage by automati
-
cally increasing engine idle speed. You may
notice several consecutive increases in idle
speed, up to a maximum of 1,450 RPM, as the
system will attempt to utilize the smallest
increase in idle speed necessary to maintain
normal system voltage. The idle speed will
return to normal when either the electrical load
is removed, or when the brake pedal is applied.
NOTE:
For instrument cluster display messages
related to the vehicle's exhaust system, refer to
“Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” for further infor -
mation.
5

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