2021 RAM PROMASTER light

150SAFETY
ELECTRONIC BRAKE CONTROL (EBC)
S
YSTEM
Your vehicle is equipped with an advanced
Electronic Brake Control (EBC) system that
includes the Brake Assist System (BAS) and
Electronic Stability Control (ESC), Hill Start
Assist (HSA), Traction Control System (TCS), and
Trailer Sway Control (TSC). These systems
complement the Anti-Lock Brake System (ABS)
by optimizing the vehicle braking capability
during emergency braking maneuvers.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s
braking capability during emergency braking
maneuvers. The system detects an emergency
braking situation by sensing the rate and
amount of brake application and then applies
optimum pressure to the brakes. This can help
reduce braking distances. The BAS
complements the Anti-Lock Brake System
(ABS). Applying the brakes very quickly results
in the best BAS assistance. To receive the
benefit of the system, you must apply
continuous braking pressure during the
stopping sequence (do not “pump” the brakes). Do not reduce brake pedal pressure unless
braking is no longer desired. Once the brake
pedal is released, the BAS is deactivated.
Crosswind Assist (CWA)
CWA helps keep your vehicle from drifting out of
its lane due to unexpected crosswinds by
means of targeted braking of individual wheels.
The system will provide automatic stability
assistance to counteract the effect of strong
side wind. If a strong lateral wind is detected,
front and rear brakes on the affected side are applied, creating a steering effect that mitigates
the cross wind influence. During system
intervention, the driver should perceive the
natural stable handling feel of the vehicle.
Crosswind Assist will activate automatically
when the vehicle reaches speeds above
approximately 43 mph (70 km/h). When the
system is activated, the ESC Warning Light in
the instrument cluster will blink to warn the
driver.
Electronic Stability Control (ESC)
ESC enhances directional control and stability
of the vehicle under various driving conditions.
ESC corrects for over/under steering 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
position.
Understeer – when the vehicle is turning less
than appropriate for the steering wheel
position.
WARNING!
The Brake Assist System (BAS) cannot
prevent the natural laws of physics from
acting on the vehicle, nor can it increase the
traction afforded by prevailing road
conditions. BAS cannot prevent collisions,
including those resulting from excessive
speed in turns, driving on very slippery
surfaces, or hydroplaning. The capabilities of
a BAS-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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152SAFETY
ESC Partial Off
This mode is entered by momentarily pushing
the ESC OFF button.
When in the “Partial Off” mode, the TCS portion
of ESC, except for the “limited slip” feature
described in the TCS section, has been disabled
and the ESC OFF Indicator Light will be
illuminated. When in the “Partial Off” mode,
ESC will operate without engine torque
management. This mode is intended to be used
if the vehicle is in deep snow, sand or gravel
conditions and more wheel spin than ESC would
normally allow is required to gain traction.
To turn ESC on again, momentarily push the
ESC OFF button. This will restore the normal
“ESC On” mode of operation. NOTE:
To improve the vehicle's traction when driving
with snow chains, or starting off in deep snow,
sand or gravel, it may be desirable to switch to
the “Partial Off” mode by pushing the ESC OFF
button. Once the situation requiring ESC to be
switched to the “Partial Off” mode is overcome,
turn ESC back on by momentarily pushing the
ESC OFF button. This may be done while the
vehicle is in motion.ESC Activation/Malfunction Indicator Light
And ESC OFF Indicator Light
The ESC Activation/Malfunction
Indicator Light in the instrument
cluster will come on when the ignition
is turned to the ON mode. It should go
out with the engine running. If the ESC
Activation/Malfunction Indicator Light comes
on continuously with the engine running, a
malfunction has been detected in the ESC
system. If this light remains on after several
ignition cycles, and the vehicle has been driven
several miles (kilometers) at speeds greater
than 30 mph (48 km/h), see an authorized
dealer as soon as possible to have the problem
diagnosed and corrected.
The ESC Activation/Malfunction Indicator Light
starts to flash as soon as the tires lose traction
and the ESC system becomes active. The ESC
Activation/Malfunction Indicator Light also
flashes when 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!
When in “Partial Off” mode, the TCS func -
tionality of ESC, (except for the limited slip
feature described in the TCS section), has
been disabled and the ESC OFF Indicator
Light will be illuminated. When in “Partial
Off” mode, the engine power reduction
feature of TCS is disabled, and the
enhanced vehicle stability offered by the
ESC system is reduced.
Trailer Sway Control (TSC) is disabled when
the ESC system is in the “Partial Off” mode.

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SAFETY153
The ESC OFF Indicator Light indicates
that the Electronic Stability Control
(ESC) is in a reduced mode.
NOTE:
The ESC Activation/Malfunction Indicator
Light and the ESC OFF Indicator Light come
on momentarily each time the ignition switch
is placed in the ON position.
Each time the ignition is placed in the ON
position, the ESC system will be on even if it
was turned off previously.
The ESC system will make buzzing or clicking
sounds when it is active. This is normal; the
sounds will stop when ESC becomes inactive
following the maneuver that caused the ESC
activation.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver
when starting a vehicle from a stop on a hill.
HSA will maintain the level of brake pressure
the driver applied for a short period of time after
the driver takes their foot off of the brake pedal.
If the driver does not apply the throttle during
this short period of time, the system will release
brake pressure and the vehicle will roll down the
hill. The system will release brake pressure in
proportion to the amount of throttle applied as
the vehicle starts to move in the intended
direction of travel.
HSA Activation Criteria
The following criteria must be met in order for
HSA to activate:
The vehicle must be stopped.
The vehicle must be on a 6% (approximate)
grade or greater hill.

Gear selection matches vehicle uphill direction
(i.e., vehicle facing uphill is in forward gear;
vehicle backing uphill is in REVERSE gear).

HSA will work in REVERSE and all forward gears
when the activation criteria have been met. The
system will not activate if the vehicle is placed
in NEUTRAL or PARK.
WARNING!
There may be situations on minor hills with a
loaded vehicle, or while pulling a trailer, when
the system will not activate and slight rolling
may occur. This could cause a collision with
another vehicle or object. Always remember
the driver is responsible for braking the
vehicle.
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154SAFETY
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
brake pressure is applied to the slipping
wheel(s) and engine power is reduced, 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. This feature remains
active even if the ESC is in the “Partial Off”
mode.
The ESC Activation/Malfunction Indicator Light
(in the instrument cluster) will start to flash as
soon as the tires lose traction and the wheels
begin to spin. This indicates that the TCS is
active. If the indicator light flashes 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, and do not switch off the ESC
or TCS.
Trailer Sway Control (TSC) — If Equipped
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
The system may reduce engine power and apply
the brake of the appropriate wheel(s) to
counteract the sway of the trailer.
WARNING!
If you use a trailer brake controller with your
trailer, the trailer brakes may be activated
and deactivated with the brake switch. If
so, there may not be enough brake pres -
sure to hold both the vehicle and the trailer
on a hill when the brake pedal is released.
In order to avoid rolling down an incline
while resuming acceleration, manually acti -
vate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the trans -
mission in PARK.
Failure to follow these warnings can result
in a collision or serious personal injury.
WARNING!
The TCS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded.
The TCS cannot prevent collisions,
including those resulting from excessive
speed in turns, or hydroplaning.
The capabilities of a TCS-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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SAFETY155
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 78.
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” mode.AUXILIARY DRIVING SYSTEMS
BLIND SPOT MONITORING (BS M) — IF
E
QUIPPED
The BSM system 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. The BSM detection zone covers approximately
one lane width on both sides of the vehicle 12 ft
(3.8 m). The zone length starts at the outside
rear view mirror and extends approximately
10 ft (3 m) beyond the rear fascia/bumper of
the vehicle. The BSM system monitors the
detection zones on both sides of the vehicle
when the vehicle speed reaches approximately
6 mph (10 km/h) or higher and will alert the
driver of vehicles in these areas.
NOTE:
The BSM system DOES NOT alert the driver
about rapidly approaching vehicles that are
outside the detection zones.
The Blind Spot Monitoring (BSM) system may
experience dropouts (blinking on and off) of
the side mirror Warning Indicator lamps
when a motorcycle or any small object
remains at the side of the vehicle for
extended periods of time (more than a couple
of seconds).
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.
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156SAFETY
The vehicle’s taillights, where the radar sensors
are located, must remain free of snow, ice, and
dirt/road contamination so that the BSM
system can function properly. Do not block the
taillights with foreign objects (bumper stickers,
bicycle racks, etc.).

Radar Sensor Locations

If the system detects degraded performance
due to contamination or foreign objects, a
message will warn you of a blocked sensor and
the warning indicators in the side view mirrors
will be on. The warning indicators will remain
illuminated until blockage clearing conditions
are met. First clear the taillights around the
sensors of the blockage. After removing the
blockage, the following procedure can be used
to reset the system, cycle the ignition from ON
to OFF and then back ON. If the blockage message is still present after
cycling the ignition and driving in traffic, check
again for a blockage.
The BSM system notifies the driver of objects in
the detection zones by illuminating the BSM
Warning Light located in the outside mirrors in
addition to sounding an audible (chime) alert
and reducing the radio volume Ú
page 158.

Warning Light Location

The BSM system monitors the detection zone
from three different entry points (side, rear,
front) while driving to see if an alert is
necessary. The BSM system will issue an alert
during these types of zone entries. Entering From The Side
Vehicles that move into your adjacent lanes
from either side of the vehicle.

Side Monitoring

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SAFETY157
Entering From The Rear
Vehicles that come up from behind your vehicle
on either side and enter the rear detection zone
with a relative speed of less than 30 mph
(48 km/h).

Rear Monitoring

Overtaking Traffic
If you pass another vehicle slowly with a relative
speed less than 15 mph (24 km/h) and the
vehicle remains in the blind spot for
approximately 1.5 seconds, the warning light
will be illuminated. If the difference in speed
between the two vehicles is greater than
15 mph (24 km/h), the warning light will not
illuminate.
Overtaking/Approaching
Overtaking/Passing

The BSM system is designed not to issue an
alert on stationary objects such as guardrails,
posts, walls, foliage, berms, snow banks, car
washes etc. However, occasionally the system
may alert on such objects. This is normal
operation and your vehicle does not require
service. The BSM system will not alert you of objects that
are traveling in the opposite direction of the
vehicle in adjacent lanes Ú
page 274.

Opposing Traffic

WARNING!
The Blind Spot Monitoring system is only an
aid to help detect objects in the blind spot
zones. The BSM system is not designed to
detect pedestrians, bicyclists, or animals.
Even if your vehicle is equipped with the BSM
system, always check your vehicle’s mirrors,
glance over your shoulder, and use your turn
signal before changing lanes. Failure to do so
can result in serious injury or death.
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158SAFETY
Rear Cross Path (RCP)
RCP is intended to aid the driver when backing
out of parking spaces where their vision of
oncoming vehicles may be blocked. Proceed
slowly and cautiously out of the parking space
until the rear end of the vehicle is exposed. The
RCP system will then have a clear view of the
cross traffic, and if an oncoming vehicle is
detected, alert the driver.

RCP Detection Zones

RCP monitors the rear detection zones on both
sides of the vehicle, for objects that are moving
toward the side of the vehicle with a minimum
speed of approximately 3 mph (5 km/h), to
objects moving a maximum of approximately
20 mph (32 km/h), such as in parking lot
situations. When RCP is on and the vehicle is in REVERSE
(R), the driver is alerted using both the visual
and audible alarms, including reducing the
radio volume.
NOTE:
In a parking lot situation, oncoming vehicles can
be blocked by vehicles parked on either side. If
the sensors are blocked by other structures or
vehicles, the system will not be able to alert the
driver.
Blind Spot Modes
Blind Spot has three selectable modes of
operation that are available in the Uconnect
system.
Blind Spot Alert Lights Only
When operating in Blind Spot Alert mode, the
BSM system will provide a visual alert in the
appropriate side view mirror based on a
detected object. However, when the system is
operating in Rear Cross Path (RCP) mode, the
system will respond with both visual and
audible alerts when a detected object is
present. Whenever an audible alert is
requested, the radio is muted.
Blind Spot Alert Lights/Chime
When operating in Blind Spot Alert Lights/
Chime mode, the BSM system will provide a
visual alert in the appropriate side view mirror
based on a detected object. If the turn signal is
then activated, and it corresponds to an alert
present on that side of the vehicle, an audible
chime will also be sounded. Whenever a turn
signal and detected object are present on the
same side at the same time, both the visual and
audible alerts will be issued. In addition to the
audible alert the radio (if on) will also be muted.
WARNING!
Rear Cross Path Detection (RCP) is not a
backup aid system. It is intended to be used
to help a driver detect an oncoming vehicle in
a parking lot situation. Drivers must be
careful when backing up, even when using
RCP. 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. Failure to do so can result in
serious injury or death.

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