2021 RAM CHASSIS CAB Owners Manual

STARTING AND OPERATING175
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

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176STARTING AND OPERATING
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 target
vehicle 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.
NOTE:
On tight turns ACC performance may be limited.
The driver must maintain control of the vehicle,
remain alert, and be ready to apply the brakes if
needed.

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.

NOTE:
The driver must maintain control of the vehicle,
remain alert, and be ready to apply the brakes if
needed.

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
illustration shown, 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

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STARTING AND OPERATING177
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
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
Ú

page 449.

Stationary Object And Stationary Vehicle Example
PARKSENSE FRONT/REAR PARK ASSIST —
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). For limitations of this
system and recommendations, see
Ú
page 182.

ParkSense will retain the system state (enabled
or disabled) from the previous 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 at one of these gear selector positions,
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 when the vehicle is
in REVERSE, 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).
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178STARTING AND OPERATING
PARKSENSE SENSORS
For the 3500, 4500 and 5500 Chassis Cab
vehicles, the rear ParkSense sensors are
shipped loose. Please refer to the Ram Body
Builders Guide for more information.
The four ParkSense sensors are to be located in
the rear fascia/bumper, and monitor the area
behind the vehicle that is within the sensors’
field of view.
The sensors can detect obstacles from
approximately 12 inches (30 cm) up to
79 inches (200 cm) from the rear fascia/
bumper in the horizontal direction, depending
on the location, type and orientation of the
obstacle.
NOTE:
If equipped as a dually, the ParkSense system
has six rear sensors to assist in detection
around the dually flares.
The six ParkSense sensors, located in the front
fascia/bumper, monitor the area in front of the
vehicle that is within the sensors’ field of view.
The sensors can detect obstacles from
approximately 12 inches (30 cm) up to 47 inches
(120 cm) from the front fascia/bumper in the
horizontal direction, depending on the location,
type and orientation of the obstacle.

PARKSENSE WARNING DISPLAY

The ParkSense Warning screen is located within
the instrument cluster display

Ú
page 90. 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 and/or right rear
regions based on the obstacle’s distance and
location relative to the vehicle.

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STARTING AND OPERATING179
Front/Rear ParkSense Arcs
1 — No Tone/Solid Arc 6 — Fast Tone/Flashing Arc
2 — No Tone/Flashing Arc 7 — Fast Tone/Flashing Arc
3 — Fast Tone/Flashing Arc 8 — Slow Tone/Solid Arc
4 — Continuous Tone/Flashing Arc 9 — Slow Tone/Solid Arc
5 — Continuous Tone/Flashing Arc 10 — Single 1/2 Second Tone/Solid Arc
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180STARTING AND OPERATING
If an obstacle is detected in the left and/or right rear region, the display will show a single arc in the left and/or right rear region 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.
The vehicle is close to the obstacle when the display shows one flashing arc and sounds a continuous tone. The following chart shows the warning alert
operation when the system is detecting an obstacle:
WARNING ALERTS FOR REAR
Rear Distance
(inches/cm) Greater than
79 inches (200 cm) 79-59 inches
(200-150 cm) 59-47 inches
(150-120 cm) 47-39 inches
(120-100 cm) 39-25 inches
(100-65 cm) 25-12 inches
(65-30 cm) Less than
12 inches (30 cm)
Audible Alert Chime NoneSingle 1/2
Second Tone Slow
Slow FastFast Continuous
Arcs-Left None NoneNoneNoneNone 6th Flashing 5th Flashing
Arcs-Center None 10th Solid 9th Solid 8th Solid 7th Flashing 6th Flashing 5th Flashing Arcs-Right None NoneNoneNoneNone 6th Flashing 5th Flashing
Radio Volume Reduced No
Yes YesYesYesYesYes

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STARTING AND OPERATING181
NOTE:
ParkSense will reduce the volume of the radio,
if on, when the system is sounding an audio
tone.
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
Ú
page 228.
ENABLING AND DISABLING 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 gear selector is moved to REVERSE
and the Front or Rear system is disabled, the
instrument cluster display will show a vehicle graphic with an “Off” message overlay over the
system that is off (Front or Rear system). This
vehicle graphic will be displayed for as long as
the vehicle is in REVERSE.
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.
WARNING ALERTS FOR FRONT
Front Distance
(inches/cm) Greater than 47 inches
(120 cm) 47-39 inches
(120-100 cm) 39-25 inches
(100-65 cm) 25-12 inches
(65-30 cm) Less than 12 inches
(30 cm)
Audible Alert Chime NoneNoneNone FastContinuous
Arcs-Left NoneNoneNone3rd Flashing 4th Flashing
Arcs-Center None1st Solid2nd Flashing 3rd Flashing4th Flashing
Arcs-Right NoneNoneNone3rd Flashing 4th Flashing
Radio Volume Reduced No
NoNo Yes Yes
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182STARTING AND OPERATING
SERVICE THE PARKSENSE PARK ASSIST
S
YSTEM
During vehicle start up, when the Front/Rear
ParkSense System has detected a faulted
condition, the instrument cluster display will
show the "Front/Rear ParkSense Unavailable
Service Required" or the "Front/Rear
ParkSense Unavailable Wipe Sensors"
message.
When the gear selector is moved into REVERSE,
a vehicle graphic will show in the instrument
cluster display, along with the display overlay
“Wipe Sensors.” If the system needs service,
the display overlay will read “Service.” Under
this condition, ParkSense will not operate.
If "Front/Rear ParkSense Unavailable Wipe
Sensors" appears in the instrument cluster
display make sure the outer surface and the
underside of the rear 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. If "Front/Rear ParkSense Unavailable Service
Required" appears in the instrument cluster
display, see an 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.
Otherwise, you could damage the sensors.
PARKSENSE SYSTEM USAGE
P
RECAUTIONS
NOTE:
Ensure that the front and rear bumpers are
free of snow, ice, mud, dirt and debris to keep
the ParkSense system operating properly.

Jackhammers, large trucks, and other vibrations
could affect the performance of ParkSense.
When you move the gear selector to the
REVERSE position and Front or Rear ParkSense
is turned off, the instrument cluster display will
show "Off" on the vehicle graphic arcs. 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 within
18 inches (45 cm) from the rear fascia/
bumper. Failure to do so can result in the
system misinterpreting a close obstacle as a
sensor problem, causing the “Front/Rear
ParkSense Unavailable Service Required”
message to be appear in the instrument
cluster display.

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