2021 RAM CHASSIS CAB coolant temperature

GETTING TO KNOW YOUR INSTRUMENT PANEL97
Right Side — If Equipped
None
Range
Average Econ
Menu Icon
Coolant Temperature
Oil Temperature
Transmission Temperature
Oil Life
Fuel Filter Life — If Equipped
Lower Left — If Equipped
None
Compass
Outside Temp
Time
Range To Empty
Average Econ
Current Econ
Trip A Distance
Trip B Distance
Trailer Trip
Trailer Brake
Oil Pressure
Coolant Temperature
Oil Temperature
Battery Voltage
Transmission Temperature
Oil Life
Exhaust Brake — If Equipped
Turbo Boost — If Equipped
Fuel Filter Life — If Equipped
Lower Right — If Equipped
None
Compass
Outside Temp
Time
Range To Empty
Average Econ
Current Econ
Trip A Distance
Trip B Distance
Trailer Trip
Trailer Brake
Oil Pressure
Coolant Temperature
Oil Temperature
Battery Voltage
Transmission Temperature
Oil Life
Exhaust Brake — If Equipped
Turbo Boost — If Equipped
Fuel Filter Life — If Equipped
Restore Defaults
Cancel
Restore
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GETTING TO KNOW YOUR INSTRUMENT PANEL103
Exhaust Filter Full — Power Reduced See
Dealer — This message indicates the PCM
has derated the engine to limit the likelihood
of permanent damage to the after-treatment
system. If this condition is not corrected and
a dealer service is not performed, extensive
exhaust after-treatment damage can occur.
To correct this condition it will be necessary
to have your vehicle serviced by an autho-
rized dealer.
NOTE:
Failing to follow the oil change indicator,
changing your oil and resetting the oil change
indicator by 0 miles remaining will prevent
the diesel exhaust filter from performing it's
cleaning routine. This will shortly result in a
Malfunction Indicator Light (MIL) and reduced
engine power. Only an authorized dealer will be
able to correct this condition.Cold Ambient Derate Mode Messages
The vehicle will display messages when a
derate (engine power reduction) is activated
to protect the engine during start up in cold
ambient temperatures.
Engine Power Reduced During Warm up —
This message will display during start up
when the ambient temperature is between
10°F (-12°C) and -10°F (-23°C).
Engine Power Reduced Up To 30 Sec
(Seconds) During Warm up — This message
will display during start up when the ambient
temperature is between -10°F (-23°C) and
-25°F (-32°C).
Engine Power Reduced Up To 2 Min
(Minutes) During Warm up — This message
will display during start up when the ambient
temperature is -25°F (-32°C) and below.
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 approximately two
minutes under more severe cold conditions.
Coolant Low
— This telltale will turn on to indi -
cate the vehicle coolant level is low. Refer to
“Dealer Service” in “Servicing And Mainte -
nance” for more information.
Diesel Exhaust Fluid (DEF) Warning
Messages
There are four different messages which are
displayed if the vehicle detects that the DEF
system has been filled with a fluid other than
DEF, has experienced component failures, or
when tampering has been detected. The vehicle
may be limited to a maximum speed of 5 mph
(8 km/h) if the DEF system is not serviced
within less than 200 miles (322 km) of the fault
being detected.
When the DEF system needs to be serviced the
following warnings will display:

DEF Low Refill Soon — This message will
display when the low level is reached, during
vehicle start up, and with increased frequency
during vehicle operation. It will be accompa -
nied by a single chime. Approximately
5 gallons (19 Liters) of DEF is required to

CAUTION!
See an authorized dealer, as damage to
the exhaust system could occur soon with
continued operation.
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108GETTING TO KNOW YOUR INSTRUMENT PANEL
Vehicles equipped with the Anti-Lock Brake
System (ABS) are also equipped with Electronic
Brake Force Distribution (EBD). In the event of
an EBD failure, the Brake Warning Light will turn
on along with the ABS Light. Immediate repair to
the ABS system is required.

Operation of the Brake Warning Light can be
checked by turning the ignition switch from the
OFF position to the ON/RUN position. The light
should illuminate for approximately two seconds.
The light should then turn off unless the parking
brake is applied or a brake fault is detected. If the
light does not illuminate, have the light inspected
by an authorized dealer.

The light also will turn on when the parking
brake is applied with the ignition switch in the
ON/RUN position. NOTE:
This light shows only that the parking brake is
applied. It does not show the degree of brake
application.
Hood Open Warning Light
This warning light will illuminate when
the hood is ajar/open and not fully
closed.
NOTE:
If the vehicle is moving, there will also be a
single chime.
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
overheated 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 Air Conditioning
(A/C) system is on, turn it off. Also, shift the
transmission into NEUTRAL and idle the vehicle.
If the temperature reading does not return to
normal, turn the engine off immediately and call
for service Ú
page 346.
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
electrical 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.
WARNING!
Driving a vehicle with the red brake light on is
dangerous. Part of the brake system may
have failed. It will take longer to stop the
vehicle. You could have a collision. Have the
vehicle checked immediately.

21_DPF_OM_EN_USC_t.book Page 108

STARTING AND OPERATING125
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 6 of
“Keyless Enter-N-Go Starting Procedure –
Engine Manifold Air Temperature 0°F To 66°F
(–18°C to 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 an 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.
NORMAL STARTING PROCEDURE —
E
NGINE MANIFOLD AIR TEMPERATURE
A
BOVE 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
transmission. 3. Place the ignition switch in the ON position
and watch the instrument panel cluster
lights.
4. Place the ignition switch in the START position 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.
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 Ú page 375.
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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126STARTING AND OPERATING
STARTING PROCEDURE — ENGINE
M
ANIFOLD 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 Ú page 90. When
engine temperatures fall below 66°F (19°C)
the “Wait To Start” telltale will remain on indi -
cating the intake air heater system is active.
Follow the steps in the “Normal Starting”
procedure 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. 3. After the “Wait to Start” telltale goes off,
place the ignition switch in the START
position. 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 0°F To 66°F (–18°C to 19°C).”

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 Ú
page 375.
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.

21_DPF_OM_EN_USC_t.book Page 126

STARTING AND OPERATING127
STARTING PROCEDURE — ENGINE
M
ANIFOLD 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,
excessive 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.

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 is 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 Ú
page 378.

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 0°F to 60°F (-18°C to 19°C).”

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STARTING AND OPERATING131
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 approximately two minutes under more
severe cold conditions.
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 two hours, the system will automatically
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 km/h). 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 automatically
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
Ú
page 90.
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STARTING AND OPERATING133
STOPPING THE ENGINE
Idle the engine a few minutes before routine shutdown. After full load operation, idle the engine three to five minutes before shutting
it down. This idle period will allow the lubricating oil and coolant to carry excess heat away from the combustion chamber, bearings, internal
components, and turbocharger. This is especially important for turbocharged, charge air-cooled engines. Refer to the following chart for proper
engine shutdown:
IDLE SHUTDOWN
This feature can be enabled so that the truck will automatically shutdown when the truck has been idling for a set period of time when the engine is at
operating temperature. Idle time can be set in 5 minute increments between
5 and 60 minutes. See an authorized dealer to enable this feature.
NOTE:
The idle shut down timer is disabled while the PTO (Power Take-off) is active.
Driving Condition Load Turbocharger Temperature Idle Time (min.) Before Engine Shutdown
Stop and Go EmptyCool Less than One
Stop and Go Medium - One
Highway Speeds MediumWarm Two
City Traffic Maximum GCWR - Three
Highway Speeds Maximum GCWR - Four
Uphill Grade Maximum GCWR Hot Five
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