2021 RAM 1500 warning lights

GETTING TO KNOW YOUR INSTRUMENT PANEL135
Wait To Start Light — If Equipped
This indicator light will illuminate for
approximately two seconds when the
ignition is turned to the RUN position.
Its duration may be longer based on
colder operating conditions. Vehicle will not
initiate start until telltale is no longer displayed
Ú page 146.
NOTE:
The “Wait To Start” telltale may not illuminate if
the intake manifold temperature is warm
enough.
Water In Fuel Indicator Light — If Equipped
The “Water In Fuel Indicator Light” will
illuminate when there is water
detected in the fuel filter. If this light
remains on, DO NOT start the vehicle
before you drain the water from the fuel filter to
prevent engine damage, and please see an
authorized dealer.GREEN INDICATOR LIGHTS
Adaptive Cruise Control (ACC) Set With
Target Light — If Equipped
This will display when the ACC is set
and a target vehicle is detected
Ú page 179.
Adaptive Cruise Control (ACC) Set With No
Target Detected Indicator Light — If
Equipped
This light will turn on when the ACC is
SET and there is no target vehicle
detected Ú page 179.
ECO Mode Indicator Light
This light will turn on when ECO Mode
is active.
Park/Headlight On Indicator Light
This indicator light will illuminate
when the park lights or headlights are
turned on.
LaneSense Indicator Light — If Equipped
The LaneSense indicator light
illuminates solid green when both
lane markings have been detected
and the system is “armed” and ready
to provide visual and torque warnings if an
unintentional lane departure occurs
Ú page 199.
CAUTION!
The presence of water in the fuel system
circuit may cause severe damage to the
injection system and irregular engine
operation. If the indicator light is illuminated,
contact an authorized dealer as soon as
possible to bleed the system. If the above
indications come on immediately after
refuelling, water has probably been poured
into the tank: switch the engine off
immediately and contact an authorized
dealer.
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21_DT_OM_EN_USC_t.book Page 135

GETTING TO KNOW YOUR INSTRUMENT PANEL137
Hill Descent Control (HDC) Indicator Light
— If Equipped
This indicator shows when the HDC
feature is turned on. The lamp will be
on solid when HDC is armed. HDC can
only be armed when the transfer case
is in the “4WD LOW” position and the vehicle
speed is less then 20 mph (32 km/h). If these
conditions are not met while attempting to use
the HDC feature, the HDC indicator light will
flash on/off.
LaneSense Indicator Light — If Equipped
When the LaneSense system is ON,
but not armed, the LaneSense
indicator light illuminates solid white.
This occurs when only left, right, or
neither lane line has been detected. If a single
lane line is detected, the system is ready to
provide only visual warnings if an unintentional
lane departure occurs on the detected lane line
Ú page 199.
BLUE INDICATOR LIGHTS
High Beam Indicator Light
This indicator light will illuminate to
indicate that the high beam
headlights are on. With the low beams
activated, push the multifunction
lever forward (toward the front of the vehicle) to
turn on the high beams. Pull the multifunction
lever rearward (toward the rear of the vehicle) to
turn off the high beams. If the high beams are
off, pull the lever toward you for a temporary
high beam on, “flash to pass” scenario.
ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated
Onboard Diagnostic system called OBD II. This
system monitors the performance of the
emissions, engine, and transmission control
systems. When these systems are operating
properly, your vehicle will provide excellent
performance and fuel economy, as well as
engine emissions well within current
government regulations. If any of these systems require service, the OBD
II system will turn on the Malfunction Indicator
Light (MIL). It will also store diagnostic codes
and other information to assist your service
technician in making repairs. Although your
vehicle will usually be drivable and not need
towing, see an authorized dealer for service as
soon as possible.
CAUTION!
Prolonged driving with the MIL on could
cause further damage to the emission
control system. It could also affect fuel
economy and driveability. The vehicle must
be serviced before any emissions tests can
be performed.
If the MIL is flashing while the vehicle is
running, severe catalytic converter damage
and power loss will soon occur. Immediate
service is required.
3

21_DT_OM_EN_USC_t.book Page 137

146STARTING AND OPERATING
(Continued)
COLD WEATHER OPERATION (BELOW
–22°F O
R −30°C)
To ensure reliable starting at these
temperatures, use of an externally powered
electric engine block heater (available from an
authorized dealer) is recommended.
AFTER STARTING
The idle speed is controlled automatically, and
it will decrease as the engine warms up.
STARTING FLUIDS — DIESEL ENGINE
O
NLY
The engine is equipped with a glow plug
preheating system. If the instructions in this
manual are followed, the engine should start in
all conditions and no type of starting fluid
should be used.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the diesel engine is
operating.
All message center lights are off.
Malfunction Indicator Light (MIL) is off.
Engine Oil Pressure telltale is not illuminated.
Voltmeter operation:
The voltmeter may show a gauge fluctuation at
various engine temperatures. This is caused by
the glow plug heating system. The number of
cycles and the length of the cycling operation is
controlled by the engine control module. Glow
plug heater operation can run for several
minutes, once the heater operation is complete
the voltmeter needle will stabilize.
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 make
sure the wireless ignition node is in the
“OFF” mode, remove the key fob from the
vehicle and lock the 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 chil-
dren, 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.
WARNING! (Continued)

21_DT_OM_EN_USC_t.book Page 146

162STARTING AND OPERATING
NOTE:
The 4WD High and 4WD Low positions are
designed for loose, slippery road surfaces
only. Driving in the 4WD High and 4WD Low
positions on dry, hard surfaced roads may
cause increased tire wear and damage to the
driveline components.
The transfer case N (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 N (Neutral) position
is to be used for recreational towing only
Úpage 231.
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:

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 the transfer case does not shift into the
desired position, one or more of the following
events may occur:

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

2. The newly selected position indicator light will continue to flash.
3. If the transfer case will not shift, a message
will appear on the cluster stating the 4WD
shift has canceled.
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.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly and that service is required. 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
circumference 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.
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.

21_DT_OM_EN_USC_t.book Page 162

164STARTING AND OPERATING
NOTE:
The 4WD High and 4WD Low positions are
designed for loose, slippery road surfaces
only. Driving in the 4WD High and 4WD Low positions on dry hard surfaced roads may
cause increased tire wear and damage to the
driveline components.
The transfer case N (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 N
(Neutral) position is to be used for recre
-
ational towing only Ú page 231.
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(4WD High, 4WD Low, and 4WD Auto) 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:

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 the transfer case does not shift into the
desired position, one or more of the following
events may occur:

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

2. The newly selected position indicator light will continue to flash.
3. If the transfer case will not shift, there will
be a cluster message stating the 4WD shift
has canceled.
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.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly and that service is required.
WARNING!
You or others could be injured or killed if
you leave the vehicle unattended with the
transfer case in the N (Neutral) position
without first fully engaging the parking
brake. The transfer case N (Neutral) posi -
tion disengages both the front and rear
drive shaft from the powertrain, and will
allow the vehicle to roll, even if the trans -
mission is in PARK. The parking brake
should always be applied when the driver is
not in the vehicle.
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.

21_DT_OM_EN_USC_t.book Page 164

STARTING AND OPERATING167
to Normal Height Mode, push the height
selector switch up once while in Entry/Exit or
drive the vehicle over 15 mph (24 km/h).
Entry/Exit mode may not be available due to
vehicle payload, an instrument cluster
message will be displayed when this occurs
Úpage 114.
NOTE:
Entry/Exit mode may be achieved using your
key fob for easier entry/loading Ú page 17.
The system requires that the ignition be in the
ON/RUN position or the engine running for all
user requested changes. When lowering the
vehicle, all of the doors must be closed. If a door
is opened at any time while the vehicle is
lowering, the change will not be completed until
the open door(s) is closed. This system uses a lifting and lowering pattern
which keeps the headlights from incorrectly
shining into oncoming traffic. When raising the
vehicle, the rear of the vehicle will move up first
and then the front. When lowering the vehicle,
the front will move down first and then the rear.
After the engine is turned off, it may be noticed
that the air suspension system operates briefly;
this is normal. The system is correcting the
position of the vehicle to ensure a proper
appearance.
To assist with changing a spare tire, the air
suspension system has a feature which allows
the automatic leveling to be disabled
Ú
page 114.
NOTE:
If equipped with a touchscreen radio, all
enabling/disabling of air suspension features
must be done through the radio Ú page 237.AIR SUSPENSION MODES
The air suspension system has multiple modes
to protect the system in unique situations. The
engine should be running to change between
Air Suspension Modes.
Automatic AERO Mode
To improve aerodynamics, the air suspension
system has a feature which will put the vehicle
into AERO height automatically Úpage 114.
Automatic Aero Mode may be disabled through
vehicle settings in the Uconnect Radio (if
equipped) Ú page 237.
Tire Jack Mode
To assist with changing a tire, the air
suspension system has a feature which allows
the automatic leveling to be disabled
Ú page 237.
Transport Mode
For towing your vehicle with four wheels off the
road, the air suspension system has a feature
which will put the vehicle into Entry/Exit height
and disable the automatic load leveling system
Ú page 237.
CAUTION!
When in ENTRY/EXIT setting, be aware of your
surroundings, you may not have the
clearance required for certain areas and
vehicle damage may occur.
WARNING!
The air suspension system uses a high
pressure volume of air to operate the system.
To avoid personal injury or damage to the
system, see an authorized dealer for service.
4

21_DT_OM_EN_USC_t.book Page 167

STARTING AND OPERATING171
This system uses a lifting and lowering pattern
which keeps the headlights from incorrectly
shining into oncoming traffic. When raising the
vehicle, the rear of the vehicle will move up first
and then the front. When lowering the vehicle,
the front will move down first and then the rear.
After the engine is turned off, it may be noticed
that the air suspension system operates briefly;
this is normal. The system is correcting the
position of the vehicle to ensure a proper
appearance.
To assist with changing a spare tire, the air
suspension system has a feature which allows
the automatic leveling to be disabled
Úpage 237.
NOTE:
If equipped with a touchscreen radio, all
enabling/disabling of air suspension features
must be done through the radio Ú page 237.AIR SUSPENSION MODES
The Air Suspension system has multiple modes
to protect the system in unique situations:
AERO Mode
To improve aerodynamics, the air suspension
system has a feature which will put the vehicle
into AERO height automatically Úpage 114.
Tire Jack Mode
To assist with changing a tire, the air
suspension system has a feature which allows
the automatic leveling to be disabled
Ú page 237.
Transport Mode
For towing your vehicle with four wheels off the
road, the air suspension system has a feature
which will put the vehicle into Entry/Exit height
and disable the automatic load leveling system
Ú page 237.
Wheel Alignment Mode
Before performing a wheel alignment, this
mode must be enabled Ú page 237.Protection Strategy
In order to “protect” the air suspension system,
the vehicle will disable load leveling as required
(suspension overloaded, battery charge low,
etc.). Load leveling will automatically resume as
soon as system operation requirements are
met. See an authorized dealer if system does
not resume.
NOTE:
For towing with air suspension Ú
page 214.
INSTRUMENT CLUSTER DISPLAY
M
ESSAGES
When the appropriate conditions exist, a
message will appear in the instrument cluster
display Ú page 114.
An audible chime will be heard whenever a
system error has been detected.
See an authorized dealer for system service if
normal operation does not resume.
WARNING!
The air suspension system uses a high
pressure volume of air to operate the system.
To avoid personal injury or damage to the
system, see an authorized dealer for service.
4

21_DT_OM_EN_USC_t.book Page 171

STARTING AND OPERATING185
The maximum braking applied by ACC is limited;
however, the driver can always apply the brakes
manually, if necessary.
NOTE:
The brake lights will illuminate whenever the
ACC system applies the brakes.
A Proximity Warning will alert the driver if ACC
predicts that its maximum braking level is not
sufficient to maintain the set distance. If this
occurs, a visual alert “BRAKE” will flash in the
instrument cluster display and a chime will
sound while ACC continues to apply its
maximum braking capacity.
NOTE:
The “BRAKE!” Screen in the instrument cluster
display is a warning for the driver to take action
and does not necessarily mean that the
Forward Collision Warning system is applying
the brakes autonomously.
Overtake Aid
When driving with Adaptive Cruise Control (ACC)
engaged, and following a vehicle, the system
will provide an additional acceleration up to the
ACC set speed to assist in passing the vehicle. This additional acceleration is triggered when
the driver utilizes the left turn signal and will
only be active when passing on the left hand
side.
ACC Operation At Stop
If the ACC system brings your vehicle to a
standstill while following the vehicle in front,
your vehicle will resume motion without any
diver intervention if the vehicle in front starts
moving within two seconds.
If the vehicle in front does not start moving
within two seconds of your vehicle coming to a
standstill, the driver will either have to push the
RES (resume) button, or apply the accelerator
pedal to reengage the ACC to the existing set
speed.
NOTE:
After the ACC system holds your vehicle at a
standstill for approximately three consecutive
minutes, the parking brake will be activated,
and the ACC system will be cancelled.
While ACC is holding your vehicle at a standstill,
if the driver seat belt is unbuckled or the driver
door is opened, the parking brake will be
activated, and the ACC system will be cancelled.
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. ice
WARNING!
When the ACC system is resumed, the driver
must ensure that there are no pedestrians,
vehicles or objects in the path of the vehicle.
Failure to follow these warnings can result in
a collision and death or serious personal
injury.
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