2021 RAM 1500 sensor

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.

21_DT_OM_EN_USC_t.book Page 186

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.

21_DT_OM_EN_USC_t.book Page 190

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

21_DT_OM_EN_USC_t.book Page 193

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.

21_DT_OM_EN_USC_t.book Page 194

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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STARTING AND OPERATING199
The system will cancel the maneuver if the
vehicle speed exceeds 5 mph (7 km/h)
during active steering guidance into the
parking space. The system will provide a
warning to the driver at 3 mph (5 km/h) that
tells them to slow down. The driver is then
responsible for completing the maneuver if
the system is canceled.
If the system is canceled during the
maneuver for any reason, the driver must
take control of the vehicle.
LANESENSE — IF EQUIPPED
LANESENSE OPERATION
The LaneSense system is operational at speeds
above 37 mph (60 km/h) and below 112 mph
(180 km/h). The LaneSense system uses a
forward looking camera to detect lane markings
and measure vehicle position within the lane
boundaries. When both lane markings are detected and the
driver drifts out of the lane (no turn signal
applied), the LaneSense system provides a
haptic warning in the form of torque applied to
the steering wheel, as well as a visual warning
in the instrument cluster display, to prompt the
driver to remain within the lane boundaries.
The driver may manually override the haptic
warning by applying force into the steering
wheel at any time.
When only a single lane marking is detected
and the driver drifts across the lane marking (no
turn signal applied), the LaneSense system
provides a visual warning through the
instrument cluster display to prompt the driver
to remain within the lane.
When only a single lane marking is detected, a
haptic or a torque warning will not be provided.
NOTE:
When operating conditions have been met, the
LaneSense system will monitor if the driver’s
hands are on the steering wheel and provide an
audible and visual warning to the driver if
removed. The system will cancel if the driver
does not return their hands to the wheel.
WARNING!
Drivers must be careful when performing
parallel or perpendicular parking maneuvers
even when using the ParkSense Active Park
Assist system. Always check carefully behind
and in front of your vehicle, look behind and
in front of you, and be sure to check for
pedestrians, animals, other vehicles,
obstructions, and blind spots before backing
up and moving forward. 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.
CAUTION!
The ParkSense Active Park Assist system is
only a parking aid and it is unable to recog
-
nize every obstacle, including small obsta -
cles. 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 prox -
imity.
The vehicle must be driven slowly when
using the ParkSense Active Park Assist
system in order to be able to stop in time
when an obstacle is detected. It is recom -
mended that the driver looks over his/her
shoulder when using the ParkSense Active
Park Assist system.4

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312SAFETY
Electronic Brake Force Distribution (EBD)
EBD manages the distribution of the braking
torque between the front and rear axles by
limiting braking pressure to the rear axle. This is
done to prevent overslip of the rear wheels to
avoid vehicle instability, and to prevent the rear
axle from entering the Anti-Lock Brake System
(ABS) before the front axle.
Electronic Roll Mitigation (ERM)
The ERM system anticipates the potential for
wheel lift by monitoring the driver’s steering
wheel input and the speed of the vehicle. When
ERM determines that the rate of change of the
steering wheel angle and vehicle’s speed are
sufficient to potentially cause wheel lift, it then
applies the appropriate brake and may also
reduce engine power to lessen the chance that
wheel lift will occur. ERM can only reduce the
chance of wheel lift occurring during severe or
evasive driving maneuvers; it cannot prevent
wheel lift due to other factors, such as road
conditions, leaving the roadway, striking objects
or other vehicles.
Electronic Stability Control (ESC)
ESC enhances directional control and stability
of the vehicle under various driving conditions.
ESC corrects for oversteering or understeering
of the vehicle by applying the brake of the
appropriate wheel(s) to counteract the above
conditions. Engine power may also be reduced
to help the vehicle maintain the desired path.
Oversteer — when the vehicle is turning more
than appropriate for the steering wheel posi -
tion.
Understeer — when the vehicle is turning less
than appropriate for the steering wheel posi -
tion.
ESC uses sensors in the vehicle to determine
the vehicle path intended by the driver and
compares it to the actual path of the vehicle.
When the actual path does not match the
intended path, ESC applies the brake of the
appropriate wheel to assist in counteracting the
oversteer or understeer condition.
The ESC Activation/Malfunction Indicator Light
located in the instrument cluster will start to
flash as soon as the ESC system becomes
active. The ESC Activation/Malfunction
Indicator Light also flashes when the TCS is
active. If the ESC Activation/Malfunction
Indicator Light begins to flash during
acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to
adapt your speed and driving to the prevailing
road conditions.
WARNING!
Many factors, such as vehicle loading, road
conditions and driving conditions, influence
the chance that wheel lift or rollover may
occur. ERM cannot prevent all wheel lift or roll
overs, especially those that involve leaving
the roadway or striking objects or other
vehicles. The capabilities of an
ERM-equipped vehicle must never be
exploited in a reckless or dangerous manner
which could jeopardize the user's safety or
the safety of others.

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318SAFETY
Ready Alert Braking (RAB)
RAB may reduce the time required to reach full
braking during emergency braking situations. It
anticipates when an emergency braking
situation may occur by monitoring how fast the
throttle is released by the driver. The Electronic
Brake Control System will prepare the brake
system for a panic stop.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
the TCS may apply brake pressure to the
spinning wheel(s) and/or reduce engine power
to provide enhanced acceleration and stability.
A feature of the TCS, Brake Limited Differential
(BLD), functions similarly to a limited slip
differential and controls the wheel spin across a
driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will
apply the brake of the spinning wheel. This will
allow more engine torque to be applied to the
wheel that is not spinning. BLD may remain
enabled even if TCS and Electronic Stability
Control (ESC) are in reduced modes.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda -
tions Ú page 214.
When TSC is functioning, the ESC Activation/
Malfunction Indicator Light will flash, the engine
power may be reduced and you may feel the
brakes being applied to individual wheels to
attempt to stop the trailer from swaying. TSC is
disabled when the ESC system is in the “Partial
Off” or “Full Off” modes.AUXILIARY DRIVING SYSTEMS
BLIND SPOT MONITORING (BSM) — IF
E
QUIPPED
BSM uses two radar sensors, located inside the
taillights, to detect highway licensable vehicles
(automobiles, trucks, motorcycles, etc.) that
enter the blind spot zones from the rear/front/
side of the vehicle.

Rear Detection Zones

When the vehicle is started, the BSM Warning
Light will momentarily illuminate in both outside
rearview mirrors to let the driver know that the
system is operational. The BSM system sensors
operate when the vehicle is in any forward gear
or REVERSE and enters standby mode when the
vehicle is in PARK.
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and
adjust the trailer load to eliminate trailer
sway.

21_DT_OM_EN_USC_t.book Page 318