brake RAM 1500 2021 Workshop Manual

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.
4

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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.
4

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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.
4

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STARTING AND OPERATING193
Front Park Assist Audible Alerts
ParkSense will turn off the Front Park Assist
audible alert (chime) after approximately three
seconds when an obstacle has been detected,
the vehicle is stationary, and brake pedal is
applied.
Adjustable Chime Volume Settings
The Front and Rear chime volume settings are
programmable through the Uconnect system
Úpage 237.
ENABLING AND DISABLING FRONT
A
ND/OR REAR PARKSENSE
Front ParkSense can be enabled and disabled
with the Front ParkSense switch.
Rear ParkSense can be enabled and disabled
with the Rear ParkSense switch.
When the Front or Rear ParkSense
switch is pushed to disable the
system, the instrument cluster display
Úpage 114 will show a vehicle
graphic of the Front or Rear ParkSense on/off
state for two seconds. When the gear selector is moved to REVERSE
and the Front or Rear system is disabled, the
instrument cluster display will show a vehicle
graphic with “OFF” on the corresponding side.
This vehicle graphic will be displayed for as long
as the vehicle is in REVERSE.
NOTE:
Arc alerts from the enabled ParkSense system,
will interrupt the five second messages, and the
instrument cluster display will show the vehicle
graphic with the corresponding arcs and “OFF”
message.
The Front or Rear ParkSense switch LED will be
on when Front or Rear ParkSense is disabled or
requires service. The Front or Rear ParkSense
switch LED will be off when the Front or Rear
system is enabled. If the Front or Rear
ParkSense switch is pushed, and the system
requires service, the Front or Rear ParkSense
switch LED will blink momentarily, and then the
LED will be on.
SERVICE THE PARKSENSE PARK ASSIST
S
YSTEM
During vehicle start up, when the ParkSense
System has detected a faulted condition, the
instrument cluster will actuate a single chime,
once per ignition cycle, and it will display the
"PARKSENSE UNAVAILABLE WIPE REAR
SENSORS", "PARKSENSE UNAVAILABLE WIPE
FRONT SENSORS", or the "PARKSENSE
UNAVAILABLE SERVICE REQUIRED" message
for five seconds. When the gear selector is
moved to REVERSE and the system has
detected a faulted condition, the instrument
cluster display will display a "WIPE OFF"
message on the corresponding blocked system
while the vehicle is in REVERSE. The system will
continue to provide arc alerts for the side that is
functioning properly.
If "PARKSENSE UNAVAILABLE WIPE REAR
SENSORS" or "PARKSENSE UNAVAILABLE WIPE
FRONT SENSORS" appears in the instrument
cluster display make sure the outer surface and
the underside of the rear fascia/bumper and/or
front fascia/bumper is clean and clear of snow,
ice, mud, dirt or other obstruction and then
cycle the ignition. If the message continues to
appear see an authorized dealer.
4

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194STARTING AND OPERATING
NOTE:
Water from a car wash or road slush in freezing
weather may also cause sensors to become
blocked.
If the "PARKSENSE UNAVAILABLE SERVICE
REQUIRED" message appears in the instrument
cluster display, see your authorized dealer.
CLEANING THE PARKSENSE SYSTEM
Clean the ParkSense sensors with water, car
wash soap and a soft cloth. Do not use rough or
hard cloths. Do not scratch or poke the sensors.
PARKSENSE SYSTEM USAGE
P
RECAUTIONS
NOTE:
Ensure that the front and rear fascias/
bumpers are free of snow, ice, mud, dirt and
debris to keep the ParkSense system oper -
ating properly.
Jackhammers, large trucks, and other vibra -
tions could affect the performance of Park -
Sense.
When you turn Front or Rear ParkSense off,
the instrument cluster display will show a
vehicle graphic of the Front or Rear Park -
Sense on/off state for two seconds. Further -
more, once you turn Front or Rear ParkSense
off, it remains off until you turn it on again,
even if you cycle the ignition.
When you move the gear selector to the
REVERSE position and Front or Rear Park -
Sense is turned off, the instrument cluster
display will show a vehicle graphic with "OFF"
in the corresponding side. This vehicle
graphic will be displayed for as long as the
vehicle is in REVERSE.
ParkSense, when on, will reduce the volume
of the radio when it is sounding a tone.
Clean the ParkSense sensors regularly,
taking care not to scratch or damage them.
The sensors must not be covered with ice,
snow, slush, mud, dirt or debris. Failure to do
so can result in the system not working prop -
erly. The ParkSense system might not detect
an obstacle behind or in front of the fascia/
bumper, or it could provide a false indication
that an obstacle is behind or in front of the
fascia/bumper.
Use the ParkSense switch to turn the Park -
Sense system off if obstacles such as bicycle
carriers, trailer hitches, etc. are placed near
the rear fascia/bumper. Failure to do so can
result in the system misinterpreting a close
obstacle as a sensor problem, causing the
“PARKSENSE UNAVAILABLE SERVICE
REQUIRED” message to be appear in the
instrument cluster display.
ParkSense should be disabled when the tail -
gate is in the lowered or open position. A
lowered tailgate could provide a false indica -
tion that an obstacle is behind the vehicle
and could also cause a false braking event.
The Rear ParkSense system will automati -
cally disable when the system detects that a
trailer with trailer brakes has been connected
to the Integrated Trailer Brake Module.
The Front ParkSense system will automati -
cally disable if a snow plow has been
connected to the vehicle.

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STARTING AND OPERATING195
PARKSENSE ACTIVE PARK ASSIST SYSTEM
— IF EQUIPPED
The ParkSense Active Park Assist system is
intended to assist the driver during parallel and
perpendicular parking maneuvers by identifying
a proper parking space, providing audible/
visual instructions, and controlling the steering
wheel. The ParkSense Active Park Assist system
is defined as “semi-automatic” since the driver
maintains control of the accelerator, gear
selector and brakes. Depending on the driver's parking maneuver selection, the ParkSense
Active Park Assist system is capable of
maneuvering a vehicle into a parallel or a
perpendicular parking space on either side (i.e.,
driver side or passenger side).
NOTE:
The driver is always responsible for
controlling the vehicle, responsible for any
surrounding objects, and must intervene as
required.
The system is provided to assist the driver
and not to substitute the driver.
During a semi-automatic maneuver, if the
driver touches the steering wheel after being
instructed to remove their hands from the
steering wheel, the system will cancel, and
the driver will be required to manually
complete the parking maneuver.
The system may not work in all conditions
(e.g. environmental conditions such as heavy
rain, snow, etc., or if searching for a parking
space that has surfaces that will absorb the
ultrasonic sensor waves).
WARNING!
Drivers must be careful when backing up
even when using ParkSense. Always check
carefully behind your vehicle, look behind
you, and be sure to check for pedestrians,
animals, other vehicles, obstructions, and
blind spots before backing up. You are
responsible for safety and must continue to
pay attention to your surroundings. Failure
to do so can result in serious injury or
death.
Before using ParkSense, it is strongly
recommended that the ball mount and
hitch ball assembly is disconnected from
the vehicle when the vehicle is not used for
towing. Failure to do so can result in injury
or damage to vehicles or obstacles
because the hitch ball will be much closer
to the obstacle than the rear fascia when
the loudspeaker sounds the continuous
tone. Also, the sensors could detect the ball
mount and hitch ball assembly, depending
on its size and shape, and give a false indi
-
cation that an obstacle is behind the
vehicle, and could cause false braking.
CAUTION!
ParkSense is only a parking aid and it is
unable to recognize every obstacle,
including small obstacles. Parking curbs
might be temporarily detected or not
detected at all. Obstacles located above or
below the sensors will not be detected
when they are in close proximity.
The vehicle must be driven slowly when
using ParkSense in order to be able to stop
in time when an obstacle is detected. It is
recommended that the driver looks over
his/her shoulder when using ParkSense.4

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196STARTING AND OPERATING
New vehicles from the dealership must have
at least 30 miles (48 km) accumulated
before the ParkSense Active Park Assist
system is fully calibrated and performs accu -
rately. This is due to the system’s dynamic
vehicle calibration to improve the perfor -
mance of the feature.
The driver must control the vehicle’s brakes.
The automatic emergency braking feature is
NOT intended to substitute for the driver
during REVERSE maneuvers.
ENABLING AND DISABLING THE
P
ARKSENSE ACTIVE PARK ASSIST
S
YSTEM
The ParkSense Active Park Assist
system can be enabled and disabled
with the ParkSense Active Park Assist
switch, located on the switch panel
below the Uconnect display.
NOTE:
If your vehicle is equipped with a 12-inch
Uconnect display, the ParkSense Active Park
Assist switch is located above the display. To enable or disable the ParkSense Active Park
Assist system, push the ParkSense Active Park
Assist switch once (LED turns on). Pushing the
switch a second time will disable the system
(LED turns off).
The ParkSense Active Park Assist system will
turn off automatically for any of the following
conditions:
Parking maneuver is completed.
Vehicle speed is greater than 18 mph
(30 km/h) when searching for a parking
space.
Vehicle speed is greater than 5 mph (7 km/h)
during active steering guidance into the
parking space.
Steering wheel is touched during active
steering guidance into the parking space.
ParkSense Front/Rear Park Assist switch is
pushed.
Driver's door is opened.
Tailgate is opened.
Electronic Stability Control/Anti-Lock Braking
System intervention.NOTE:
The ParkSense Active Park Assist system will
allow a maximum of eight shifts between DRIVE
and REVERSE. If the maneuver cannot be
completed within eight shifts, the system will
cancel and the instrument cluster display will
instruct the driver to complete the maneuver
manually.
The ParkSense Active Park Assist system will
only operate and search for a parking space
when the following conditions are present:
Gear selector is in DRIVE.
The ignition is in the ON/RUN position.
The ParkSense Active Park Assist switch is
activated.
Driver's door is closed.
Tailgate is closed.
Vehicle speed is less than 15 mph (25 km/h).
The outer surface and the underside of the
front and rear fascias/bumpers are clean
and clear of snow, ice, mud, dirt or other
obstruction.

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198STARTING AND OPERATING
When an available parking space has been
found, and the vehicle is not in position, you will
be instructed to move forward to position the
vehicle for a perpendicular or parallel parking
sequence (depending on the type of maneuver
being performed).

Space Found — Keep Moving Forward

Once the vehicle is in position, you will be
instructed to stop the vehicle’s movement and
remove your hands from the steering wheel.
When the vehicle comes to a standstill (your
hands still removed from the steering wheel),
you will be instructed to place the gear selector
into the REVERSE position.
The system may then instruct the driver to wait
for steering to complete before then instructing
to check surroundings and move backward.
Move Backward Into Parallel Parking Space
Move Backward Into Perpendicular Parking Space

The system may instruct several more gear
shifts (DRIVE and REVERSE), with hands off of
the steering wheel, before instructing the driver
to check surroundings and complete the
parking maneuver. When the vehicle is in the parking position, the
maneuver is complete and the driver will be
instructed to check the vehicle's parking
position, then shift the vehicle into PARK. The
message "Active ParkSense Complete - Check
Parking Position" will be displayed momentarily.
NOTE:
It is the driver's responsibility to use the
brake and accelerator during the semi-auto
-
matic parking maneuver.
It is the driver's responsibility to use the
brake and stop the vehicle. The driver should
check their surroundings and be prepared to
stop the vehicle either when instructed to, or
when driver intervention is required.
When the system instructs the driver to
remove their hands from the steering wheel,
the driver should check their surroundings
and begin to back up slowly.
The ParkSense Active Park Assist system will
allow a maximum of eight shifts between
DRIVE and REVERSE. If the maneuver cannot
be completed within eight shifts, the system
will cancel and the instrument cluster display
will instruct the driver to complete the
maneuver manually.

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