2021 RAM 1500 air condition

128GETTING TO KNOW YOUR INSTRUMENT PANEL
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 (N) and idle the
vehicle. If the temperature reading does not
return to normal, turn the engine off
immediately and call for service Ú page 389.
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.
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 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.
If the light continues to flash when the vehicle is
running, immediate service is required and you
may experience reduced performance, an
elevated/rough idle, or engine stall and your
vehicle may require towing. The light will come
on when the ignition is placed in the ON/RUN or
ACC/ON/RUN position and remain on briefly as
a bulb check. If the light does not come on
during starting, have the system checked by an
authorized dealer.

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GETTING TO KNOW YOUR INSTRUMENT PANEL131
Electronic Stability Control (ESC) OFF
Warning Light — If Equipped
This warning light indicates the ESC is
off.
Each time the ignition is turned to ON/RUN or
ACC/ON/RUN, the ESC system will be on, even
if it was turned off previously.
Service LaneSense Warning Light — If
Equipped
This warning light will illuminate when
the LaneSense system is not
operating and requires service.
Please contact an authorized dealer.
Low Washer Fluid Warning Light — If
Equipped
This warning light will illuminate when
the windshield washer fluid is low.
Low Fuel Warning Light
When the fuel level is less than a ¼
tank, and the Distance to Empty is
less than 50 miles, this light will turn
on and remain on until fuel is added. A single warning chime will sound with Low Fuel
Warning.
Tire Pressure Monitoring System (TPMS)
Warning Light
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
indications 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
pressure 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
pressure. 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
pressure 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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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.
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148STARTING AND OPERATING
NOTE:
Use of Climatized ULSD Fuel 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 crys -
tals 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 Ú page 471.
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).
Engine Oil Usage
For the correct engine oil viscosity Úpage 475.
Winter Front Cover

Winter Front Cover

A Winter front or cold weather cover can be
used in ambient temperatures below 32°F
(0°C), especially 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
in the full open position to allow air flow to the
cooling module and automatic transmission oil
cooler. When ambient temperatures drop below
0°F (-17°C) the four flaps need to be closed. A
suitable cold weather cover is available from a
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.
If temperatures are below 32°F (0°C), operate
the engine at moderate speeds for five minutes
before full loads are applied.
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, cylinder head
valves, and injector nozzles. Also, the unburned
fuel can enter the crankcase, diluting the oil
and causing rapid wear to the engine.
STOPPING THE ENGINE
After full load operation, idle the engine for a
few minutes before shutting it down. This idle
period will allow the lubricating oil and coolant
to carry excess heat away from the
turbocharger. Refer to the following chart for
proper engine shutdown.

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STARTING AND OPERATING153
If exceptional circumstances should make it
necessary to engage the parking brake while
the vehicle is in motion, maintain upward
pressure on the EPB switch for as long as
engagement is desired. The BRAKE telltale light
will illuminate, and a continuous chime will
sound. The rear stop lamps will also be
illuminated automatically while the vehicle
remains in motion.
To disengage the parking brake while the
vehicle is in motion, release the switch. If the
vehicle is brought to a complete stop using the
parking brake, when the vehicle reaches
approximately 3 mph, (5 km/h) the parking
brake will remain engaged. In the unlikely event of a malfunction of the EPB
system, a yellow EPB fault light will illuminate.
This may be accompanied by the BRAKE telltale
light flashing. In this event, urgent service of the
EPB system is required. Do not rely on the
parking brake to hold the vehicle stationary.
Auto Park Brake
The Electric Park Brake (EPB) can be
programmed to be applied automatically
whenever the vehicle is at a standstill and the
automatic transmission is placed in PARK. Auto
Park Brake is enabled and disabled by
customer selection through the customer
programmable features section of the Uconnect
Settings Ú
page 245.
Any single Auto Park Brake application can be
bypassed by pushing the EPB switch to the
release position while the transmission is
placed in PARK.
SafeHold
SafeHold is a safety feature of the Electric Park
Brake (EPB) system that will engage the parking
brake automatically if the vehicle is left
unsecured while the ignition is in ON/RUN. The parking brake will automatically engage if
all of the following conditions are met:
The vehicle is at a standstill.
There is no attempt to press the brake pedal
and accelerator pedal.
The seat belt is unbuckled.
The driver door is open.
SafeHold can be temporarily bypassed by
pushing the EPB switch while the driver door is
open. Once manually bypassed, SafeHold will
be enabled again once the vehicle reaches
12 mph (20 km/h) or the ignition is turned to
the OFF position and back to ON again.
Brake Service Mode
We recommend having your brakes serviced by
an authorized dealer. You should only make
repairs for which you have the knowledge and
the right equipment. You should only enter
Brake Service Mode during brake service.
When servicing your rear brakes, it may be
necessary for you or your technician to push the
rear piston into the rear caliper bore. With the
Electric Park Brake (EPB) system, this can only
be done after retracting the EPB actuator.
WARNING!
Driving the vehicle with the parking brake
engaged, or repeated use of the parking
brake to slow the vehicle may cause serious
damage to the brake system. Be sure the
parking brake is fully disengaged before
driving; failure to do so can lead to brake
failure and a collision.
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STARTING AND OPERATING165
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, 4WD Auto 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.
Shifting Procedure
If any of the requirements to select a new
transfer case position have not been met,
then the transfer case will not shift. The posi -
tion indicator light for the previous position
will remain on and the newly selected posi -
tion 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, then
the current position indicator light will turn off
and the selected position indicator light will
flash until the transfer case completes the
shift. When the shift is complete, the position
indicator light for the selected position will
stop flashing and remain on.
ACTIVE-LEVEL FOUR CORNER AIR
SUSPENSION SYSTEM — IF EQUIPPED
DESCRIPTION
The air suspension system provides full time
load leveling capability along with the benefit of
being able to adjust vehicle height by using the
toggle switch.
Air Suspension Switch

Normal Ride Height (NRH)
– This is the stan-
dard position of the suspension and is meant
for normal driving.

Off-Road 1 (OR1) (Raises the vehicle
approximately 1 inch (26 mm)) – This posi-
tion should be the primary position for all
off-road driving until Off-Road 2 (OR2) is
needed. A smoother and more comfortable
ride will result. To enter OR1, push the

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.
1 — Off-Road 2 Indicator (Customer Selectable)
2 — Off-Road 1 Indicator (Customer Selectable)
3 — Normal Ride Height Indicator (Customer Se -
lectable)
4 — Aero Mode Indicator (Customer Selectable)
5 — Entry/Exit Mode Indicator (Customer Select -
able)
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168STARTING AND OPERATING
Wheel Alignment Mode
Before performing a wheel alignment, this
mode must be enabled Úpage 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.
OPERATION

Air Suspension Switch

The indicator lamps 1 through 5 will illuminate
to show the current position of the vehicle.
Flashing indicator lamps will show a position
which the system is working to achieve. When
raising, if multiple indicator lamps are flashing,
the highest flashing indicator lamp is the
position the system is working to achieve. When
lowering, if multiple indicators are flashing, the
lowest solid indicator lamp is the position the
system is working to achieve.
Pushing the height selector up once will move
the suspension one position higher from the
current position, assuming all conditions are
met (i.e. key in ON/RUN position, engine
running, speed below threshold, etc). The height selector switch can be pushed up
multiple times, each push will raise the
requested level by one position up to a
maximum position of OR2 or the highest
position allowed based on current conditions
(i.e. vehicle speed, etc).
Pushing the height selector down once will
move the suspension one position lower from
the current level, assuming all conditions are
met (i.e. key in ON/RUN position, engine
running, doors closed, speed below threshold,
etc). The height selector switch can be pushed
down multiple times, each push will lower the
requested level by one position down to a
minimum of Entry/Exit Mode or the lowest
position allowed based on current conditions
(i.e. vehicle speed, etc.)
Automatic height changes will occur based on
vehicle speed and the current vehicle height.
The indicator lamps and instrument cluster
display messages will operate the same for
automatic changes and user requested
changes.

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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.
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