light Ram 3500 Chassis Cab 2020 Manual Online

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.
5

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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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194STARTING AND OPERATING
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the engine is oper -
ating.
All message center lights are off.
Malfunction Indicator Light (MIL) is off.
Engine oil pressure is above 10 psi (69 kPa)
at idle.
Voltmeter operation:
The voltmeter may show a gauge fluctuation at
various engine temperatures. This cycling oper -
ation is caused by the post-heat cycle of the
intake manifold heater system. The number of
cycles and the length of the cycling operation is
controlled by the engine control module.
Post-heat operation can run for several
minutes, and then the electrical system and
voltmeter needle will stabilize. The cycling action will cause temporary
dimming of the headlamps, interior lamps, and
also a noticeable reduction in blower motor
speed.
Cold Weather Precautions
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following charts suggest these options:
WARNING!
Do not leave children or animals inside
parked vehicles in hot weather. Interior
heat build up may cause serious injury or
death.
When leaving the vehicle, always remove
the key fob and lock your vehicle.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle.
Allowing children to be in a vehicle unat
-
tended is dangerous for a number of
reasons. A child or others could be seriously
or fatally injured. Children should be
warned not to touch the parking brake,
brake pedal or the gear selector. Do not
leave the key fob in or near the vehicle (or
in a location accessible to children), and do
not leave the ignition of a vehicle equipped
with Keyless Enter-N-Go in the ACC or ON/
RUN mode. A child could operate power
windows, other controls, or move the
vehicle.

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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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198STARTING 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 aftertreat -
ment system to not properly regenerate.
Extended periods of idle time should be
avoided.
The Idle-Up feature uses the Speed Control
switches 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 speed control, then push the
SET switch.

2. The engine RPM will go up to 1,100 RPM. To increase the RPM, push and hold the
ACCEL/RESUME switch and the idle speed
will increase to approximately 1,500 RPM.
To decrease the RPM, push and hold the
DECEL switch and the idle speed will
decrease to approximately 1,100 RPM.
3. To cancel the Idle–Up feature, either push the CANCEL switch, push the ON/OFF
switch, 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. Engine’s 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 aftertreatment 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.
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 espe
-
cially important for turbocharged, charge
air-cooled engines. Refer to the following chart
for proper engine shutdown:

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202STARTING AND OPERATING
ENGINE BREAK-IN RECOMMENDATIONS —
GAS ENGINE
A long break-in period is not required for the
engine and drivetrain (transmission and axle) in
your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles (100 km),
speeds up to 50 or 55 mph (80 or 90 km/h) are
desirable.
While cruising, brief full-throttle acceleration
within the limits of local traffic laws contributes
to a good break-in. Wide-open throttle accelera-
tion in low gear can be detrimental and should
be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving type
lubricant. Oil changes should be consistent with
anticipated climate conditions under which
vehicle operations will occur. For the recom -
mended viscosity and quality grades, refer to
“Fluids And Lubricants” in “Technical Specifica-
tions”. NOTE:
A new engine may consume some oil during its
first few thousand miles (kilometers) of opera
-
tion. This should be considered a normal part of
the break-in and not interpreted as a problem.
Please check your oil level with the engine oil
indicator often during the break in period. Add
oil as required.
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE
The Cummins® Turbo Diesel engine does not
require a break-in period due to its construction.
Normal operation is allowed, providing the
following recommendations are followed:
Warm up the engine before placing it under
load.
Do not operate the engine at idle for
prolonged periods.
Use the appropriate transmission gear to
prevent engine lugging.
Observe vehicle oil pressure and tempera -
ture indicators.
Check the coolant and oil levels frequently.
Vary throttle position at highway speeds
when carrying or towing significant weight.
NOTE:
Light duty operation such as light trailer towing
or no load operation will extend the time before
the engine is at full efficiency. Reduced fuel
economy and power may be seen at this time.
For additional vehicle break-in requirements,
refer to “Trailer Towing” in “Starting And Oper -
ating” of the Owner’s Manual.
Because of the construction of the Cummins®
Turbo Diesel engine, engine run-in is enhanced
by loaded operating conditions which allow the
engine parts to achieve final finish and fit during
the first 6,000 miles (10,000 km).
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.

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204STARTING AND OPERATING
(Continued)
Automatic “Smart” Exhaust Brake
Automatic “Smart” Exhaust Brake technology
delivers smoother, less aggressive exhaust
braking characteristics during downhill
descents. Although it can apply full exhaust
braking force if needed, Automatic “Smart”
Exhaust Brake may not apply obvious braking if
the vehicle speed is not increasing. Automatic
“Smart” Exhaust Brake is intended to maintain
vehicle speed, while Full Exhaust Brake is
intended to reduce vehicle speed.
Automatic “Smart” Exhaust Brake can be
enabled by pushing the exhaust brake button
(on the center stack) again anytime after the
normal Full Exhaust Brake has been turned on.
The “Exhaust Brake Indicator” in the instrument
cluster display will change from Yellow to Green
when Automatic “Smart” Exhaust Brake is
enabled. Pushing the exhaust brake button
again will toggle the exhaust brake mode to off.
PARKING BRAKE
Before leaving the vehicle, make sure that the
parking brake is fully applied. Also, be certain to
leave the transmission in PARK.The foot operated parking brake is located
below the lower left corner of the instrument
panel. To apply the park brake, firmly push the
park brake pedal fully. To release the parking
brake, pull the parking brake release handle.

Parking Brake Release

When the parking brake is applied with the igni -
tion switch ON, the “Brake Warning Light” in the
instrument cluster will illuminate.
NOTE:
When the parking brake is applied and the
transmission is placed in gear, the “Brake
Warning Light” will flash. If vehicle speed is
detected, a chime will sound to alert the
driver. Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application.
When parking on a hill, it is important to turn the
front wheels toward the curb on a downhill
grade and away from the curb on an uphill
grade. Apply the parking brake before placing
the gear selector in PARK, otherwise the load on
the transmission locking mechanism may make
it difficult to move the gear selector out of PARK.
The parking brake should always be applied
whenever the driver is not in the vehicle.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply the
parking brake fully when parked to guard
against vehicle movement and possible
injury or damage.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle. Leaving
unattended children in a vehicle is
dangerous for a number of reasons. A child
or others could be seriously or fatally
injured.

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STARTING AND OPERATING205
(Continued)
(Continued)
AUTOMATIC TRANSMISSION
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil-
dren, and do not leave a vehicle equipped
with Keyless Enter-N-Go in the ACC or ON/
RUN mode. A child could operate power
windows, other controls, or move the
vehicle.
Be sure the parking brake is fully disen
-
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.
WARNING! (Continued)
WARNING!
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
The transmission may not engage PARK if
the vehicle is moving. Always bring the
vehicle to a complete stop before shifting to
PARK, and verify that the transmission gear
position indicator solidly indicates PARK (P)
without blinking. Ensure that the vehicle is
completely stopped, and the PARK position
is properly indicated, before exiting the
vehicle.
Unintended movement of a vehicle could
injure those in or near the vehicle. As with
all vehicles, you should never exit a vehicle
while the engine is running. Before exiting a
vehicle, always come to a complete stop,
then apply the parking brake, shift the
transmission into PARK, turn the engine
OFF, and remove the key fob. When the
ignition is in the LOCK/OFF (key removal)
position, (or, with Keyless Enter-N-Go, when
the ignition is in the OFF mode) the trans -
mission is locked in PARK, securing the
vehicle against unwanted movement.
When leaving the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
Never use the PARK position as a substi -
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
WARNING! (Continued)
5

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210STARTING AND OPERATING
If the transmission temperature exceeds
normal operating limits, the powertrain
controller will modify the transmission shift
schedule and expand the range of torque
converter clutch engagement. This is done to
prevent transmission damage due to over -
heating.
If the transmission becomes extremely hot or is
in danger of overheating, the “Transmission
Temperature Warning Light” may illuminate and
the transmission may operate differently until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer
up a steep grade, or in stop-and-go traffic)
during hot weather. In these conditions, torque
converter slip can impose a significant addi -
tional heat load on the cooling system. Down -
shifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to
NEUTRAL (when stopped in heavy traffic) can
help to reduce this excess heat generation. During cold temperatures, transmission opera
-
tion may be modified depending on engine and
transmission temperature as well as vehicle
speed. This feature improves warm up time of
the engine and transmission to achieve
maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmis -
sion fluid is warm (refer to the “Note” under
“Torque Converter Clutch” in this section).
On trucks with AS66RC or AS69RC transmis -
sion, FIFTH and SIXTH gears may be inhibited
briefly on cold starts below 41°F (5°C), and
during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third
gear only. During this condition, the ability of the
vehicle to accelerate under heavily loaded
conditions may be reduced. In all cases, normal
operation will resume once the transmission
temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission remains
in third gear (for AS66RC/AS69RC transmis -
sion) regardless of which forward gear is
selected. If an AS66RC/AS69RC equipped truck enters Limp Home Mode at highway speeds, it
will initially engage fifth gear, until the vehicle
slows to a speed where third gear can be
engaged. PARK, REVERSE, and NEUTRAL will
continue to operate. The Malfunction Indicator
Light (MIL) may be illuminated. Limp Home
Mode allows the vehicle to be driven to an
authorized dealer for service without damaging
the transmission.
In the event of a momentary problem, the trans
-
mission can be reset to regain all forward gears
by performing the following steps:

1. Stop the vehicle.

2. Shift the transmission into PARK.
3. Turn the ignition to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no longer detected, the trans -
mission will return to normal operation.

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212STARTING AND OPERATING
Overdrive Operation
The automatic transmission includes an elec -
tronically controlled Overdrive (FIFTH and SIXTH
gears). The transmission will automatically shift
into Overdrive if the following conditions are
present:
The gear selector is in the DRIVE position.
The transmission fluid has reached an
adequate temperature.
The engine coolant has reached an adequate
temperature.
Vehicle speed is sufficiently high.
The TOW/HAUL switch has not been
activated.
The driver is not heavily pressing the
accelerator.
Torque Converter Clutch
A feature designed to improve fuel economy
has been included in the automatic transmis -
sion on your vehicle. A clutch within the torque
converter engages automatically at calibrated
speeds. This may result in a slightly different feeling or response during normal operation in
the upper gears. When the vehicle speed drops
or during some accelerations, the clutch auto
-
matically disengages.
NOTE:
The torque converter clutch will not engage,
until the transmission fluid and engine
coolant are warm (usually after 1 to 3 miles
(2 to 5 km) of driving). Because engine speed
is higher when the torque converter clutch is
not engaged, it may seem as if the transmis -
sion is not shifting properly when cold. This is
normal. Using the Electronic Range Select
(ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the
transmission is able to shift into and out of
Overdrive.
If the vehicle has not been driven for several
days, the first few seconds of operation after
shifting the transmission into gear may seem
sluggish. This is due to the fluid partially
draining from the torque converter into the
transmission. This condition is normal and
will not cause damage to the transmission.
The torque converter will refill within five
seconds after starting the engine.
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent trans -
mission shifting occurs, push the TOW/HAUL
switch to activate TOW/HAUL mode. This will
improve performance and reduce the potential
for transmission overheating or failure due to
excessive shifting. When operating in TOW/
HAUL mode, transmission upshifts are delayed,
and the transmission will automatically down -
shift (for engine braking) when the throttle is
closed and/or during steady braking maneu -
vers.

TOW/HAUL Switch

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