2020 Ram 3500 brake

STARTING AND OPERATING283
(Continued)
ADAPTIVE CRUISE CONTROL (ACC)
O
PERATION
The speed control buttons (located on the right
side of the steering wheel) operate the ACC
system.

Adaptive Cruise Control Buttons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 the vehicle to a complete stop
while following a target vehicle and hold
the vehicle for approximately two
seconds in the stop position. At this
point, there will be an “ACC may cancel
soon” chime and warning to the driver.
When ACC is cancelled, the system will
release the brakes and the driver must
take over braking. The system can be
resumed when the target vehicle drives
off by releasing the brake and pushing
the resume button on the steering
wheel.

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 — Adaptive Cruise Control On/Off Button
2 — Distance Button
3 — RES (+)
4 — SET (-)
5 — CANCEL
6 — Normal (Fixed Speed) Cruise Control On/Off
Button
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284STARTING AND OPERATING
NOTE:
Any chassis/suspension or tire size modifica -
tions to the vehicle will affect the performance
of the Adaptive Cruise Control and Forward
Collision Warning System.
ACTIVATING ADAPTIVE CRUISE CONTROL
(ACC)
You can only engage ACC if the vehicle speed is
above 0 mph (0 km/h).
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 Four-Wheel Drive Low.
When you apply the brakes.
When the parking brake is applied.
When the automatic transmission is in PARK,
REVERSE or NEUTRAL.
When the vehicle speed is outside of the
speed range.
When the brakes are overheated.
When the driver door is open at low speed.
When the driver seat belt is unbuckled at low
speed.
Electronic Stability Control (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.”

Adaptive Cruise Control 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.”

Adaptive Cruise Control 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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STARTING AND OPERATING285
TO SET A DESIRED ACC SPEED
When the vehicle reaches the speed desired,
push the SET (-) button and release. The
instrument cluster display will show the set
speed.
If the system is set when the vehicle speed is
below 20 mph (32 km/h), the set speed shall
be defaulted to 20 mph (32 km/h). If the
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:
ACC cannot be set if there is a stationary vehicle
in front of your vehicle in close proximity.
Remove your foot from the accelerator pedal
after the ACC has been set. If you do not, the
vehicle may continue to accelerate beyond the
set speed. If this occurs:
The message “ACC DRIVER OVERRIDE” will
display in the instrument cluster display.
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 system:
The brake pedal is applied.
The CANCEL button is pushed.
An Anti-Lock Brake System (ABS) event
occurs.
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.
Driver seat belt is unbuckled at low speeds.
Driver door is opened at low speeds.
A Trailer Sway Control (TSC) event occurs.
The driver switches ESC to Full Off mode.
The braking temperature exceeds normal
range (overheated).
The trailer brake is applied manually (if
equipped).
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 Normal (Fixed Speed) Cruise Control on/
off button is pushed.
The ignition is placed in the OFF position.
You switch to Four-Wheel Drive Low.
TO RESUME
If there is a set speed in memory push the RES
(+) button and then remove your foot from the
accelerator pedal. The instrument cluster
display will display the last set speed.
NOTE:
If your vehicle stays at standstill for longer
than two seconds, the driver will have to push
the RES (+) button to reengage the ACC to the
existing set speed.
ACC cannot be resumed if there is a
stationary vehicle in front of your vehicle in
close proximity.
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286STARTING AND OPERATING
TO VARY THE SPEED SETTING
To Increase Speed
While ACC is set, you can increase the set speed
by pushing the RES (+) button.

The speed increment shown is dependent on the
chosen speed unit of U.S. (mph) or Metric (km/h):
U.S. Speed (mph)

Pushing the RES (+) button once will result in a
1 mph increase in set speed. Each subsequent
tap of the button results in an increase of 1 mph.

If the button is continually pushed, the set
speed will continue to increase in 5 mph incre -
ments until the button is released. The increase
in set speed is reflected in the instrument
cluster display.
Metric Speed (km/h)

Pushing the RES (+) button once will result in
a 1 km/h increase in set speed. Each subse -
quent tap of the button results in an increase
of 1 km/h.
If the button is continually pushed, the set
speed will continue to increase in 10 km/h
increments until the button is released. The
increase in set speed is reflected in the
instrument cluster display.
To Decrease Speed
While ACC is set, the set speed can be
decreased by pushing the SET (-) button.
The speed decrement shown is dependent on
the chosen speed unit of U.S. (mph) or Metric
(km/h):
U.S. Speed (mph)
Pushing the SET (-) button once will result in
a 1 mph decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 mph.
If the button is continually pushed, the set
speed will continue to decrease in 5 mph
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display. Metric Speed (km/h)

Pushing the SET (-) button once will result in
a 1 km/h decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 km/h.
If the button is continually pushed, the set
speed will continue to decrease in 10 km/h
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
NOTE:
When you override and push the RES (+)
button or SET (-) button, the new set speed
will be the current speed of the vehicle.
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 a target vehicle. If an
ACC host vehicle follows a target vehicle to a
standstill, after two seconds the driver will
either have to push the RES (+) button, or
apply the accelerator pedal to reengage the
ACC to the existing set speed.
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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288STARTING AND OPERATING
The system automatically defaults to the
longest distance setting. To decrease the
distance setting, push the Distance Button and
release. Each time the button is pushed, the
distance setting decreases by one bar. Once the
shortest setting is reached, if the button is
pushed again it will reset to the default setting
(longest).
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 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. (Refer to “Activating
Adaptive Cruise Control (ACC)” in this
chapter. 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.

Brake Alert
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.
Trailer Detect — If Equipped

When a trailer is detected, the ACC system
automatically defaults to the longest setting (four
bars). The setting can be overridden by pushing
the Distance Button on the steering wheel.

OVERTAKE AID
When driving with 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.

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STARTING AND OPERATING289
ACC OPERATION AT STOP
If your ACC system brings your vehicle to a
standstill while following a vehicle ahead, your
vehicle will resume motion, without any driver
interaction, if the vehicle ahead starts moving
within two seconds.
If the target vehicle does not start moving within
two seconds of your vehicle coming to a
standstill, then ACC will cancel and the driver
must take over braking. When the target vehicle
drives off, ACC can be resumed by releasing the
brake and pushing the RES (+) button.
NOTE:
After the ACC system holds your vehicle at a
standstill for approximately two seconds, a
chime will sound and an “ACC may cancel soon”
warning will display. The brakes will release
when ACC is canceled and the driver must take
over braking.
While ACC is holding your vehicle at a standstill,
if the driver seat belt is unbuckled or the driver
door is opened, the ACC system will cancel and
the brakes will release. Driver intervention will
be required at this moment.
ADAPTIVE CRUISE CONTROL (ACC)
M
ENU
The instrument cluster display will show the
current ACC system settings. The instrument
cluster display is located in the center of the
instrument cluster. The information it displays
depends on ACC system status.
Push the Adaptive Cruise Control (ACC) on/off
button (located on the steering wheel) 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.” 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 RES (+) or the SET(-) button (located
on the steering wheel) 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.
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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STARTING AND OPERATING291
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.
The “ACC/FCW Limited Functionality Clean
Front Windshield” 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.
If weather conditions are not a factor, the driver
should examine the windshield and the camera
located on the back side of the inside rearview
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 your 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 your
authorized dealer.
PRECAUTIONS WHILE DRIVING WITH
ACC
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. 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.
Cleaning Instructions
Dust and dirt can accumulate on the cover and
block the camera lens. Clean the camera lens
with a soft microfiber cloth, being careful not to
damage or scratch the module.
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292STARTING AND OPERATING
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 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.
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

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