2021 RAM 1500 warning

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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174STARTING AND OPERATING
LIMITED-SLIP DIFFERENTIAL — IF
EQUIPPED
The limited-slip differential provides additional
traction on snow, ice, mud, sand and gravel,
particularly when there is a difference between
the traction characteristics of the surface under
the right and left rear wheels. During normal
driving and cornering, the limited-slip unit
performs similarly to a conventional differential.
On slippery surfaces, however, the differential
delivers more of the driving effort to the rear
wheel having the better traction.
The limited-slip differential is especially helpful
during slippery driving conditions. With both
rear wheels on a slippery surface, a slight
application of the accelerator will supply
maximum traction. When starting with only one
rear wheel on an excessively slippery surface,
slight momentary application of the parking
brake may be necessary to gain maximum
traction. Care should be taken to avoid sudden
accelerations when both rear wheels are on a
slippery surface. This could cause both rear
wheels to spin, and allow the vehicle to slide
sideways on the crowned surface of a road or in
a turn.
POWER STEERING
ELECTRIC POWER STEERING
The electric power steering system will provide
increased vehicle response and ease of
maneuverability. The power steering system
adapts to different driving conditions.
If the steering icon is flashing, it indicates that
the vehicle needs to be taken to the dealer for
service. It is likely the vehicle has lost power
steering assistance.If the steering icon is displayed and the “POWER
STEERING SYSTEM OVER TEMP” message is
displayed on the instrument cluster screen, this
indicates an over temperature condition in the
power steering system. Once driving conditions
are safe, pull over and let the vehicle idle for a
few moments until the icon and message turn
off Ú
page 114.
If the steering icon is displayed and the
“SERVICE POWER STEERING – ASSIST OFF”
message is displayed the instrument cluster
screen, this indicates the vehicle needs to be
taken to the dealer for service Ú page 114.
NOTE:
Even if the power steering assistance is no
longer operational, it is still possible to steer
the vehicle. Under these conditions there will
be a substantial increase in steering effort,
especially at low speeds and during parking
maneuvers.
If the condition persists, see an authorized
dealer for service.
WARNING!
When servicing vehicles equipped with a
limited-slip or locking differential never run
the engine with one rear wheel off the ground
since the vehicle may drive through the rear
wheel remaining on the ground and result in
unintended movement.

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STARTING AND OPERATING177
TO MANUALLY TURN ON THE STOP
S
TART SYSTEM
Push the Stop/Start OFF switch (located on the
switch bank). The light on the switch will turn
off.
SYSTEM MALFUNCTION
If there is a malfunction in the Stop/Start
system, the system will not shut down the
engine. A “SERVICE STOP/START SYSTEM”
message will appear in the instrument cluster
display Ú page 126.
The system will need to be checked by an
authorized dealer.
CRUISE CONTROL SYSTEMS — IF EQUIPPED
Your vehicle may be equipped with the Cruise
Control system, or the Adaptive Cruise Control
(ACC) system:
Cruise Control for cruising at a constant
preset speed.
Adaptive Cruise Control (ACC) for maintaining
a set distance between you and the vehicle
ahead using Fixed Speed Cruise Control to
automatically adjust the preset speed. NOTE:
In vehicles equipped with ACC, if an ACC
distance is not set, Fixed Speed Cruise Control
will not detect vehicles directly ahead of you.
Always be aware of the mode selected.
CRUISE CONTROL — IF EQUIPPED
When engaged, the Cruise Control takes over
accelerator operations at speeds greater than
20 mph (32 km/h).
The Cruise Control buttons are located on the
right side of the steering wheel.

Cruise Control Buttons
NOTE:
In order to ensure proper operation, the Cruise
Control system has been designed to shut down
if multiple Cruise Control functions are operated
at the same time. If this occurs, the Cruise
Control system can be reactivated by pushing
the Cruise Control on/off button and resetting
the desired vehicle set speed.
To Activate
Push the on/off button to activate the Cruise
Control. The cruise indicator light in the
instrument cluster display will illuminate. To
turn the system off, push the on/off button a 1 — CANC/Cancel
2 — SET (+)/Accel
3 — On/Off
4 — RES/Resume
5 — SET (-)/Decel
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.
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178STARTING AND OPERATING
second time. The cruise indicator light will turn
off. The system should be turned off when not in
use.
To Set A Desired Speed
Turn the Cruise Control on.
When the vehicle has reached the desired
speed, push the SET (+) or SET (-) button and
release. Release the accelerator and the
vehicle will operate at the selected speed.
NOTE:
The vehicle should be traveling at a steady
speed and on level ground before pushing the
SET (+) or SET (-) button.
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
When the Cruise Control is set, you can increase
speed by pushing the SET (+) button, or
decrease speed by pushing the SET (-) button.
U.S. Speed (mph)
Pushing the SET (+), or SET (-) button once
will result in a 1 mph speed adjustment. Each
subsequent tap of the button results in an
adjustment of 1 mph.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
Metric Speed (km/h)
Pushing the SET (+), or SET (-) button once
will result in a 1 km/h speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 km/h.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
To Accelerate For Passing
While the Cruise Control is set, press the
accelerator to pass as you would normally.
When the pedal is released, the vehicle will
return to the set speed.
Using Cruise Control On Hills
The transmission may downshift on hills to
maintain the vehicle set speed.
NOTE:
The Cruise Control system maintains speed up
and down hills. A slight speed change on
moderate hills is normal.
On steep hills, a greater speed loss or gain may
occur so it may be preferable to drive without
Cruise Control.
WARNING!
Leaving the Cruise Control system on when
not in use is dangerous. You could
accidentally set the system or cause it to go
faster than you want. You could lose control
and have an accident. Always ensure the
system is off when you are not using it.
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.

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STARTING AND OPERATING179
(Continued)
To Resume Speed
To resume a previously set speed, push the RES
button and release. Resume can be used at any
speed above 20 mph (32 km/h).
To Deactivate
A tap on the brake pedal, pushing the CANC
(cancel) button, or normal brake pressure while
slowing the vehicle will deactivate the Cruise
Control system without erasing the set speed
from memory.
The following conditions will also deactivate the
Cruise Control system without erasing the set
speed from memory:
Vehicle parking brake is applied
Stability event occurs
Gear selector is moved out of DRIVE
Engine overspeed occurs
Pushing the on/off button or placing the ignition
in the OFF position, erases the set speed from
memory.
ADAPTIVE CRUISE CONTROL (ACC) — IF
E
QUIPPED
Adaptive Cruise Control (ACC) increases the
driving convenience provided by Cruise Control
while traveling on highways and major
roadways. However, it is not a safety system
and not designed to prevent collisions. The
Cruise Control function performs differently
Ú page 177.
ACC will allow you to keep Cruise Control
engaged in light to moderate traffic conditions
without the constant need to reset your speed.
ACC utilizes a radar sensor and a forward facing
camera designed to detect a vehicle directly
ahead of you to maintain a set speed.
NOTE:
If the ACC sensor detects a vehicle ahead,
ACC will apply limited braking or acceleration
(not to exceed the original set speed) auto -
matically to maintain a preset following
distance, while matching the speed of the
vehicle ahead.
Any chassis/suspension or tire size modifica -
tions to the vehicle will affect the perfor -
mance of the Adaptive Cruise Control and
Forward Collision Warning system.
Fixed Speed Cruise Control alone (an ACC
distance not set) will not detect vehicles
directly ahead of you. Always be aware of the
mode selected.
WARNING!
Adaptive Cruise Control (ACC) is a conve -
nience system. It is not a substitute for
active driver involvement. It is always the
driver’s responsibility to be attentive of
road, traffic, and weather conditions,
vehicle speed, distance to the vehicle
ahead; and, most importantly, brake opera -
tion to ensure safe operation of the vehicle
under all road conditions. Your complete
attention is always required while driving to
maintain safe control of your vehicle.
Failure to follow these warnings can result
in a collision and death or serious personal
injury.
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180STARTING AND OPERATING
(Continued)
Adaptive Cruise Control (ACC) Operation
The buttons on the right side of the steering
wheel operate the Adaptive Cruise Control
system.
Adaptive Cruise Control Buttons

Adaptive Cruise Control (ACC) Menu
The instrument cluster display will show the
current ACC system settings. The information it
displays depends on ACC system status.
Push the Adaptive Cruise Control (ACC) on/off
button until one of the following appears in the
instrument cluster display:
Adaptive Cruise Control Off
When ACC is deactivated, the display will read
“Adaptive Cruise Control Off.”
The ACC system:
Does not react to pedestrians,
oncoming vehicles, and stationary
objects (e.g., a stopped vehicle in a
traffic jam or a disabled vehicle).
Cannot take street, traffic, and weather
conditions into account, and may be
limited upon adverse sight distance
conditions.
Does not always fully recognize
complex driving conditions, which can
result in wrong or missing distance
warnings.
Will bring your vehicle to a complete
stop while following a vehicle ahead
and hold your vehicle for approximately
three minutes in the stop position. If the
vehicle ahead does not start moving
within three minutes the parking brake
will be activated, and the ACC system
will be cancelled.
WARNING!
(Continued)
You should switch off the ACC system:
When driving in fog, heavy rain, heavy
snow, sleet, heavy traffic, and complex
driving situations (i.e., in highway construc -
tion zones).
When entering a turn lane or highway off
ramp; when driving on roads that are
winding, icy, snow-covered, slippery, or
have steep uphill or downhill slopes.
When towing a trailer up or down steep
slopes.
When circumstances do not allow safe
driving at a constant speed.
WARNING! (Continued)
1 — Distance Setting Increase
2 — Adaptive Cruise Control (ACC) On/Off
3 — Distance Setting Decrease

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STARTING AND OPERATING181
Adaptive Cruise Control Ready
When ACC is activated, but the vehicle speed
setting has not been selected, the display will
read “Adaptive Cruise Control Ready.”
Adaptive Cruise Control Set
When the SET (+) or the SET (-) button is
pushed, the display will read “ACC SET.”
When ACC is set, the set speed will show in the
instrument cluster display.
The ACC screen may display once again if any of
the following ACC activity occurs:
System Cancel
Driver Override
System Off
ACC Proximity Warning
ACC Unavailable Warning
The instrument cluster display will return to the
last display selected after five seconds of no
ACC display activity.
Activating Adaptive Cruise Control (ACC)
The minimum set speed for the ACC system is
20 mph (32 km/h).
When the system is turned on and in the ready
state, the instrument cluster display will read
“ACC Ready.”
When the system is off, the instrument cluster
display will read “Adaptive Cruise Control (ACC)
Off.”
NOTE:
You cannot engage ACC under the following
conditions:
When in 4WD Low
When the brakes are applied
When the parking brake is applied
When the automatic transmission is in PARK,
REVERSE or NEUTRAL
When the vehicle speed is below the
minimum speed range
When the brakes are overheated
When the driver’s door is open at low speeds
When the driver’s seat belt is unbuckled at
low speeds
When there is a stationary vehicle in front of
your vehicle in close proximity
ESC Full Off mode is active
To Activate/Deactivate
Push and release the Adaptive Cruise Control
(ACC) on/off button. The ACC menu in the
instrument cluster displays “ACC Ready.”
To turn the system off, push and release the
Adaptive Cruise Control (ACC) on/off button
again. At this time, the system will turn off and
the instrument cluster display will show
“Adaptive Cruise Control (ACC) Off.”
WARNING!
Leaving the Adaptive Cruise Control (ACC)
system on when not in use is dangerous. You
could accidentally set the system or cause it
to go faster than you want. You could lose
control and have a collision. Always leave the
system off when you are not using it.
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182STARTING AND OPERATING
To Set A Desired ACC Speed
When the vehicle reaches the speed desired,
push the SET (+) button or the SET (-) button
and release. The instrument cluster display will
show the set speed.
NOTE:
Fixed Speed Cruise Control can be used without
an ACC distance set. To change between the
different modes, push the ACC on/off button
which turns the ACC and the Fixed Speed Cruise
Control off. Pushing the Fixed Speed Cruise
Control on/off button will result in turning on
(changing to) Fixed Speed Cruise Control mode. If ACC is set when the vehicle speed is
below
20 mph (32 km/h), the set speed will default to
20 mph (20 km/h).
NOTE:
Fixed Speed Cruise Control cannot be set below
20 mph (32 km/h).
If either system is set when the vehicle speed is
above 20 mph (32 km/h), the set speed shall
be the current speed of the vehicle.
NOTE:
Keeping your foot on the accelerator pedal
can cause the vehicle to continue to accel -
erate beyond the set speed. If this occurs, the
message “ACC DRIVER OVERRIDE” will
display in the instrument cluster display.
If you continue to accelerate beyond the set
speed while an ACC distance is also set, the
system will not be controlling the distance
between your vehicle and the vehicle ahead.
The vehicle speed will only be determined by
the position of the accelerator pedal.
To Cancel
The following conditions cancel the ACC or Fixed
Speed Cruise Control systems:
The brake pedal is applied
The CANC (cancel) button is pushed
The Anti-Lock Brake system (ABS) activates
The trailer brake is applied manually (if
equipped)
The gear selector is removed from the DRIVE
position
The Electronic Stability Control/Traction
Control System (ESC/TCS) activates
The vehicle parking brake is applied
The Trailer Sway Control (TSC) activates
The driver switches ESC to Full Off mode
The braking temperature exceeds normal
range (overheated)
The following conditions will only cancel the ACC
system:
Driver seat belt is unbuckled at low speeds
Driver door is opened at low speeds
WARNING!
In the Fixed Speed Cruise Control mode, the
system will not react to vehicles ahead. In
addition, the proximity warning does not
activate and no alarm will sound even if you
are too close to the vehicle ahead since
neither the presence of the vehicle ahead nor
the vehicle-to-vehicle distance is detected. Be
sure to maintain a safe distance between
your vehicle and the vehicle ahead. Always be
aware which mode is selected.

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