warning light RAM CHASSIS CAB 2020 Workshop Manual

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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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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STARTING AND OPERATING213
The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that TOW/
HAUL mode has been activated. Pushing the
switch a second time restores normal opera -
tion. Normal operation is always the default at
engine start-up. If TOW/HAUL mode is desired,
the switch must be pushed each time the
engine is started.
Eight-Speed Automatic Transmission — If
Equipped
The transmission is controlled using a rotary
electronic gear selector located on the instru -
ment panel. The transmission gear range
(PRND) is displayed both above the gear
selector and in the instrument cluster. To select
a gear range, simply rotate the gear selector.
You must press the brake pedal to shift the transmission out of PARK (or NEUTRAL, when
the vehicle is stopped or moving at low speeds).
To shift past multiple gear ranges at once (such
as PARK to DRIVE), simply rotate the gear
selector to the appropriate detent. Select the
DRIVE range for normal driving.
NOTE:
In the event of a mismatch between the gear
selector position and the actual transmission
gear (for example, driver selects PARK while
driving), the position indicator will blink continu
-
ously until the selector is returned to the proper
position, or the requested shift can be
completed.
The electronically-controlled transmission
adapts its shift schedule based on driver inputs,
along with environmental and road conditions.
The transmission electronics are self-cali -
brating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a
normal condition, and precision shifts will
develop within a few hundred miles (kilome -
ters).
Only shift from DRIVE to PARK or REVERSE
when the accelerator pedal is released and the
vehicle is stopped. Be sure to keep your foot on the brake pedal when shifting between these
gears.
The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE positions.
Manual downshifts can be made using the Elec
-
tronic Range Select (ERS) shift control. Pressing
the GEAR-/GEAR+ switches (on the steering
wheel) while in the DRIVE position will select the
highest available transmission gear, and will
display that gear limit in the instrument cluster
as 1, 2, 3, etc. Refer to “Electronic Range Select
(ERS) Operation” in this section for further infor -
mation. Some models will display both the
selected gear limit, and the actual current gear,
while in ERS mode.

Electronic Transmission Gear Selector

WARNING!
Do not use the “TOW/HAUL” feature when
driving in icy or slippery conditions. The
increased engine braking can cause the rear
wheels to slide, and the vehicle to swing
around with the possible loss of vehicle
control, which may cause an accident
possibly resulting in personal injury or death.
5

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216STARTING AND OPERATING
NEUTRAL (N)
Use this range when the vehicle is standing for
prolonged periods with the engine running.
Apply the parking brake and shift the transmis -
sion into PARK if you must exit the vehicle. DRIVE (D)
This range should be used for most city and
highway driving. It provides the smoothest
upshifts and downshifts, and the best fuel
economy. The transmission automatically
upshifts through all forward gears. The DRIVE
position provides optimum driving characteris
-
tics under all normal operating conditions.
When frequent transmission shifting occurs
(such as when operating the vehicle under
heavy loading conditions, in hilly terrain, trav -
eling into strong head winds, or while towing a
heavy trailer), select TOW/HAUL mode or use
the Electronic Range Select (ERS) shift control
(refer to "Electronic Range Select (ERS) Opera -
tion" in this section for further information) to
select a lower gear range. Under these condi -
tions, using a lower gear range will improve
performance and extend transmission life by
reducing excessive shifting and heat buildup.
During extremely cold temperatures
(-22°F [-30°C] or below), transmission opera -
tion may be modified depending on engine and
transmission temperature as well as vehicle
speed. Normal operation will resume once the
transmission temperature has risen to a suit -
able 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 may
operate only in certain gears, or may not shift at
all. Vehicle performance may be severely
degraded and the engine may stall. In some
situations, the transmission may not re-engage
if the engine is turned off and restarted. The
Malfunction Indicator Light (MIL) may be illumi -
nated. A message in the instrument cluster will
inform the driver of the more serious conditions,
and indicate what actions may be necessary.
In the event of a momentary problem, the trans -
mission can be reset to regain all forward gears
by performing the following steps:
NOTE:
In cases where the instrument cluster message
indicates the transmission may not re-engage
after engine shutdown, perform this procedure
only in a desired location (preferably, at an
authorized dealer).
WARNING!
Do not coast in NEUTRAL and never turn off
the ignition to coast down a hill. These are
unsafe practices that limit your response to
changing traffic or road conditions. You might
lose control of the vehicle and have a
collision.
CAUTION!
Towing the vehicle, coasting, or driving for any
other reason with the transmission in
NEUTRAL can cause severe transmission
damage. Refer to “Recreational Towing” in
“Starting And Operating” and “Towing A
Disabled Vehicle” in “In Case Of Emergency”
for further information.

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218STARTING AND OPERATING
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.

TOW/HAUL Switch

The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that TOW/
HAUL mode has been activated. Pushing the
switch a second time restores normal opera -
tion. Normal operation is always the default at
engine start-up. If TOW/HAUL mode is desired,
the switch must be pushed each time the
engine is started.
AUXILIARY SWITCHES — IF EQUIPPED
There can be up to six auxiliary switches located
in the lower switch bank of the instrument panel
which can be used to power various electronic
devices and PTO (Power Take Off) – If Equipped.
If Power Take Off is equipped, it will take the
place of the sixth Auxiliary switch. Connections
to the switches are found under the hood in the
connectors attached to the auxiliary Power
Distribution Center. You have the ability to configure the function
-
ality of the auxiliary switches via the instrument
cluster display. All switches can now be config -
ured for setting the switch type operation to
latching or momentary, power source of either
battery or ignition, and ability to hold last state
across key cycles.
NOTE:
Holding last state conditions are met when
switch type is set to latching and power source
is set to ignition.
For further information on using the auxiliary
switches, please refer to the Ram Body Builders
Guide by accessing www.rambodybuilder.com
and choosing the appropriate links.
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with
either a manually shifted transfer case or an
electronically shifted transfer case. Refer to the
operating instructions for your transfer case,
located in this section for further information.
WARNING!
Do not use the “TOW/HAUL” feature when
driving in icy or slippery conditions. The
increased engine braking can cause the rear
wheels to slide, and the vehicle to swing
around with the possible loss of vehicle
control, which may cause an accident
possibly resulting in personal injury or death.

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220STARTING AND OPERATING
This electronically shifted transfer case is
designed to be driven in the two–wheel drive
position (2WD) for normal street and highway
conditions on dry hard surfaced roads. Driving
the vehicle in 2WD will have greater fuel
economy benefits as the front axle is not
engaged in 2WD.
When additional traction is required, the
transfer case 4WD HIGH and 4WD LOW posi -
tions can be used to maximize torque to the
front driveshaft, forcing the front and rear
wheels to rotate at the same speed. This is
accomplished by pushing the desired position
on the 4WD control switch.
Refer to “Shifting Procedure” in this section for
specific shifting instructions.
The 4WD HIGH and 4WD LOW positions are
designed for loose, slippery road surfaces only.
Driving in the 4WD HIGH and 4WD LOW posi -
tions on dry hard surfaced roads may cause
increased tire wear and damage to the driveline
components. NOTE:
The transfer case Neutral button is located in
the center of the 4WD Control Switch and is
pushed by using a ballpoint pen or similar
object. The transfer case Neutral position is to
be used for recreational towing only. Refer to
“Recreational Towing” in “Starting And Oper
-
ating” for further information.
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(4WD HIGH and 4WD LOW) are located in the
instrument cluster and indicate the current and
desired transfer case selection. When you
select a different transfer case position, the
indicator lights will do the following:
If All Of The Following Shift Conditions Are Met:

1. The current position indicator light will turn off.

2. The selected position indicator light will flash until the transfer case completes the
shift.
3. When the shift is complete, the indicator light for the selected position will stop
flashing and remain on. If One Or More Of The Following Shift Conditions
Are Not Met:

1. The indicator light for the current position
will remain on.

2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift.
NOTE:
Before retrying a selection, make certain that all
the necessary requirements for selecting a new
transfer case position have been met. To retry
the selection, push the current position, wait
five seconds, and retry selection. To find the
shift requirements, refer to the “Shifting Proce-
dure” for your transfer case, located in this
section.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or illumi -
nates during driving, it means that the
four-wheel drive system is not functioning prop -
erly and that service is required.

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STARTING AND OPERATING221
NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. This could
cause damage to driveline components.
When operating your vehicle in 4WD LOW, the
engine speed is approximately three times that
of the 2WD or 4WD HIGH positions at a given
road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and circum -
ference on each wheel. Any difference in tire
size can cause damage to the drivetrain.
Because four-wheel drive provides improved
traction, there is a tendency to exceed safe
turning and stopping speeds. Do not go faster
than road conditions permit.
Shifting Procedure
NOTE:
If any of the requirements to select a new
transfer case position have not been met, the
transfer case will not shift. The position indi -
cator light for the previous position will
remain on and the newly selected position
indicator light will continue to flash until all
the requirements for the selected position
have been met.
If all the requirements to select a new
transfer case position have been met, the
current position indicator light will turn off,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain on. 2WD To 4WD HIGH
Push the desired position on the 4WD control
switch to shift the transfercase. Shifts between
2WD and 4WD HIGH can be done with the
vehicle stopped or in motion. With the vehicle in
motion, the transfer case will engage/disen
-
gage faster if you momentarily release the
accelerator pedal after turning the control
switch. If the vehicle is stopped, the ignition
switch must be in the ON position with the
engine either running or off. This shift cannot be
completed if the ignition switch is in the ACC
position.
NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD HIGH if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light
will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
WARNING!
Always engage the parking brake when
powering down the vehicle if the “SVC 4WD
Warning Light” is illuminated. Not engaging
the parking brake may allow the vehicle to roll
which may cause personal injury or death.
5

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