2021 RAM 1500 Owners Manual

STARTING AND OPERATING183
To Turn Off
The system will turn off and clear the set speed
in memory if:
The Adaptive Cruise Control (ACC) on/off
button is pushed
The Fixed Speed Cruise Control on/off button
is pushed
The ignition is placed in the OFF position
4WD Low is engaged
To Resume
If there is a set speed in memory, push the RES
(resume) button and then remove your foot
from the accelerator pedal. The instrument
cluster display will display the last set speed.
Resume can be used at any speed above
20 mph (32 km/h) when only Fixed Speed
Cruise Control is being used.
Resume can be used at any speed above 0 mph
(0 km/h) when ACC is active. NOTE:
While in ACC mode when the vehicle comes
to a complete stop longer than two seconds,
the system will cancel. The driver will have to
apply the brakes to keep the vehicle at a
standstill.
ACC cannot be resumed if there is a
stationary vehicle in front of your vehicle in
close proximity.
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
After setting a speed, you can increase the set
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 in 5 mph incre -
ments until the button is released. The new
set speed is reflected in the instrument
cluster display.
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 in 10 km/h
increments until the button is released. The
new set speed is reflected in the instrument
cluster display.
NOTE:
When you override and push the SET (+) button
or SET (-) buttons, the new set speed will be the
current speed of the vehicle.
WARNING!
The Resume function should only be used if
traffic and road conditions permit. Resuming
a set speed that is too high or too low for
prevailing traffic and road conditions could
cause the vehicle to accelerate or decelerate
too sharply for safe operation. Failure to
follow these warnings can result in a collision
and death or serious personal injury.
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184STARTING AND OPERATING
When An ACC Distance Is Also Set:
When you use the SET (-) button to decel -
erate, if the engine’s braking power does not
slow the vehicle sufficiently to reach the set
speed, the brake system will automatically
slow the vehicle.
The ACC system decelerates the vehicle to a
full stop when following the vehicle in front. If
your vehicle follows the vehicle in front to a
standstill, after two seconds 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.
The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal. In
addition, downshifting may occur while
climbing uphill or descending downhill. This
is normal operation and necessary to main -
tain set speed. When driving uphill and down -
hill, the ACC system will cancel if the braking
temperature exceeds normal range (over -
heated).
Setting The Following Distance In ACC
The specified following distance for Adaptive
Cruise Control (ACC) can be set by varying the
distance setting between four bars (longest),
three bars (long), two bars (medium) and one
bar (short). Using this distance setting and the
vehicle speed, ACC calculates and sets the
distance to the vehicle ahead. This distance
setting displays in the instrument cluster
display.

Distance Settings
To increase the distance setting, push the
Distance Increase button and release. Each
time the button is pushed, the distance setting
increases by one bar (longer).
To decrease the distance setting, push the
Distance Decrease button and release. Each
time the button is pushed, the distance setting
decreases by one bar (shorter).
If there is no vehicle ahead, the vehicle will
maintain the set speed. If a slower moving
vehicle is detected in the same lane, the
instrument cluster displays the ACC Set With
Target Detected Indicator Light, and the system
adjusts vehicle speed automatically to maintain
the distance setting, regardless of the set
speed.
The vehicle will then maintain the set distance
until:
The vehicle ahead accelerates to a speed
above the set speed.
The vehicle ahead moves out of your lane or
view of the sensor.
The distance setting is changed.
The system disengages.
1 — Longest Distance Setting (Four Bars)
2 — Long Distance Setting (Three Bars)
3 — Medium Distance Setting (Two Bars)
4 — Short Distance Setting (One Bar)

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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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186STARTING AND OPERATING
and snow, or tunnels with reflective tiles). The
ACC system will recover after the vehicle has left
these areas. Under rare conditions, when the
radar is not tracking any vehicles or objects in
its path this warning may temporarily occur.
NOTE:
If the “ACC/FCW Unavailable Wipe Front Radar
Sensor” warning is active, Fixed Speed Cruise
Control is still available.
If weather conditions are not a factor, the driver
should examine the sensor. It may require
cleaning or removal of an obstruction. The
sensor is located in the camera in the center of
the windshield, on the forward side of the
rearview mirror.
To keep the ACC system operating properly, it is
important to note the following maintenance
items:
Always keep the sensor clean. Carefully clear
the windshield.
Do not remove any screws from the sensor.
Doing so could cause an ACC system
malfunction or failure and require a sensor
realignment.
Do not attach or install any accessories near
the sensor, including transparent material.
Doing so could cause an ACC system failure
or malfunction.
When the condition that deactivated the system
is no longer present, the system will return to
the “Adaptive Cruise Control Off” state and will
resume function by simply reactivating it.
NOTE:
If the “ACC/FCW Unavailable Wipe Front
Radar Sensor” message occurs frequently
(e.g. more than once on every trip) without
any snow, rain, mud, or other obstruction,
have the radar sensor realigned at an autho -
rized dealer.
Installing a snow plow, front-end protector,
an aftermarket grille or modifying the grille is
not recommended. Doing so may block the
sensor and inhibit ACC/FCW operation. “Clean Front Windshield” Warning
The “ACC/FCW Limited Functionality Clean
Front Windshield” 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 and fog. The ACC
system may also become temporarily blinded
due to obstructions, such as mud, dirt, or ice on
windshield, driving directly into the sun and fog
on the inside of glass. In these cases, the
instrument cluster display will show “ACC/FCW
Limited Functionality Clean Front Windshield”
and the system will have degraded
performance.
This message can sometimes be displayed
while driving in adverse weather conditions. The
ACC/FCW system will recover after the vehicle
has left these areas. Under rare conditions,
when the camera is not tracking any vehicles or
objects in its path this warning may temporarily
occur.

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STARTING AND OPERATING187
If weather conditions are not a factor, the driver
should examine the windshield and the camera
located on the back side of the inside rear view
mirror. They may require cleaning or removal of
an obstruction.
When the condition that created limited
functionality is no longer present, the system
will return to full functionality.
NOTE:
If the “ACC/FCW Limited Functionality Clean
Front Windshield” message occurs frequently
(e.g. more than once on every trip) without any
snow, rain, mud, or other obstruction, have the
windshield and forward facing camera
inspected at an authorized dealer.
Service ACC/FCW Warning
If the system turns off, and the instrument
cluster displays “ACC/FCW Unavailable Service
Required” or “Cruise/FCW Unavailable Service
Required”, there may be an internal system
fault or a temporary malfunction that limits ACC
functionality. Although the vehicle is still
drivable under normal conditions, ACC will be
temporarily unavailable. If this occurs, try
activating ACC again later, following an ignition
cycle. If the problem persists, see an authorized
dealer.Precautions While Driving With ACC
NOTE:
Aftermarket add-ons such as snow plows, lift
kits, and brush/grille bars can hinder module
performance. Ensure the radar/camera has
no obstructions in the field of view.
Height modifications can limit module perfor -
mance and functionality.
Do not put stickers or easy passes over the
camera/radar field of view.
Any modifications to the vehicle that may
obstruct the field of view of the radar/camera
are not recommended.
In certain driving situations, ACC may have
detection issues. In these cases, ACC may
brake late or unexpectedly. The driver needs to
stay alert and may need to intervene. The
following are examples of these types of
situations:
Towing A Trailer
ACC while towing a trailer is recommended only
with an Integrated Trailer Brake Controller.
Aftermarket trailer brake controllers will not
activate the trailer brakes when ACC is braking. Offset Driving
ACC may not detect a vehicle in the same lane
that is offset from your direct line of travel, or a
vehicle merging in from a side lane. There may
not be sufficient distance to the vehicle ahead.
The offset vehicle may move in and out of the
line of travel, which can cause your vehicle to
brake or accelerate unexpectedly.

Offset Driving Condition Example

Turns And Bends
When driving on a curve with ACC engaged, the
system may decrease the vehicle speed and
acceleration for stability reasons, with no
vehicle in front detected. Once the vehicle is out
of the curve the system will resume your original
set speed. This is a part of normal ACC system
functionality.
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188STARTING AND OPERATING
NOTE:
On tight turns ACC performance may be limited.

Turn Or Bend Example

Using ACC On Hills
When driving on hills, ACC may not detect a
vehicle in your lane. Depending on the speed,
vehicle load, traffic conditions, and the
steepness of the hills, ACC performance may be
limited.
ACC Hill Example

Lane Changing
ACC may not detect a vehicle until it is
completely in the lane in which you are
traveling. In the lane changing example below,
ACC has not yet detected the vehicle changing
lanes and it may not detect the vehicle until it's
too late for the ACC system to take action. ACC
may not detect a vehicle until it is completely in
the lane. There may not be sufficient distance to
the lane-changing vehicle. Always be attentive
and ready to apply the brakes if necessary.
Lane Changing Example

Narrow Vehicles
Some narrow vehicles traveling near the outer
edges of the lane or edging into the lane are not
detected until they have moved fully into the
lane. There may not be sufficient distance to the
vehicle ahead.

Narrow Vehicle Example

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STARTING AND OPERATING189
Stationary Objects And Vehicles
ACC does not react to stationary objects and
stationary vehicles. For example, ACC will not
react in situations where the vehicle you are
following exits your lane and the vehicle ahead
is stopped in your lane. Always be attentive and
ready to apply the brakes if necessary
Úpage 482.

Stationary Object And Stationary Vehicle Example

PARKSENSE FRONT/REAR PARK ASSIST
SYSTEM — IF EQUIPPED
The ParkSense Park Assist system provides
visual and audible indications of the distance
between the rear and/or front fascia/bumper
and a detected obstacle when backing up or
moving forward (e.g. during a parking maneuver). If your vehicle is equipped with the
automatic braking function, the vehicle brakes
may be automatically applied and released
when the vehicle is in REVERSE if the system
detects a possible collision with an obstacle.
NOTE:
The driver can disable the automatic braking
function by turning ParkSense off via the
ParkSense switch. The driver can also over
-
ride automatic braking by changing the gear
or by pressing the gas pedal over 90% of its
capacity during the braking event.
Automatic brakes will not be available if the
vehicle is in 4WD Low.
Automatic brakes will not be available if ESC
is not available.
Automatic brakes will not be available if there
is a faulted condition detected with the Park -
Sense Park Assist system or the Braking
System.
The automatic braking function may only be
applied if the vehicle deceleration is not
enough to avoid colliding with a detected
obstacle.
The automatic braking function may not be
applied fast enough for obstacles that move
toward the rear of the vehicle from the left
and/or right sides.
The automatic braking function can be
enabled/disabled from the Customer
Programmable Features section of the
Uconnect system.
ParkSense will retain its last known configu -
ration state for the automatic braking func -
tion through ignition cycles.
Trailer hitch ball assembly may cause false
braking events if left attached after towing.
The automatic braking function is intended to
assist the driver in avoiding possible collisions
with detected obstacles when backing up in
REVERSE gear.
NOTE:
The system is provided to assist the driver
and not to substitute the driver.
The driver must stay in full control of the
vehicle's acceleration and braking and is
responsible for the vehicle's movements.
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190STARTING AND OPERATING
For limitations of this system and usage
precautions, see Úpage 194.
ParkSense will retain the last system state
(enabled or disabled) from the last ignition cycle
when the ignition is placed in the ON/RUN
position.
ParkSense can be active only when the gear
selector is in REVERSE or DRIVE. If ParkSense is
enabled while in one of these gears, the system
will remain active until the vehicle speed is
increased to approximately 7 mph (11 km/h) or
above. A warning will appear in the instrument
cluster display indicating the vehicle is above
ParkSense operating speed. The system will
become active again if the vehicle speed is
decreased to speeds less than approximately
6 mph (9 km/h).PARKSENSE SENSORS
The four ParkSense sensors (six if equipped
with Active Parksense), located in the front
fascia/bumper, monitor the area in front of the
vehicle that is within the sensors’ field of view,
and the four ParkSense sensors, located in the
rear fascia/bumper, monitor the area behind
the vehicle that is within the sensors’ field of
view. The front sensors can detect obstacles
from approximately 12 inches (30 cm) up to
47 inches (120 cm) from the front fascia/
bumper. The rear sensors can detect obstacles
from approximately 12 inches (30 cm) up to
79 inches (200 cm). These distances depend
on the location, type and orientation of the
obstacle in the horizontal direction.
PARKSENSE WARNING DISPLAY
The ParkSense Warning screen is located within
the instrument cluster display Ú page 114. It
provides visual warnings to indicate the
distance between the rear fascia/bumper and/
or front fascia/bumper and the detected
obstacle.
PARKSENSE DISPLAY
The warning display will turn on indicating the
system status when the vehicle is in REVERSE
or when the vehicle is in DRIVE and an obstacle
has been detected.
The system will indicate a detected obstacle by
showing a single arc in the left, right, or center
regions based on the obstacle’s distance and
location relative to the vehicle.
If an obstacle is detected in the left, right, or
center regions, the display will show a single arc
in the left and/or right regions and the system
will produce a tone. As the vehicle moves closer
to the obstacle, the display will show the single
arc moving closer to the vehicle and the tone
will change from a single 1/2 second tone to
slow, to fast, to continuous.

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