2021 RAM 1500 light

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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SAFETY313
(Continued)
ESC Operating Modes
Depending upon model and mode of operation,
the ESC system may have multiple operating
modes. ESC On
This is the normal operating mode for the ESC.
Whenever the vehicle is started, the ESC system
will be in this mode. This mode should be used
for most driving conditions. Alternate ESC
modes should only be used for specific reasons
as noted in the following paragraphs.
Partial Off
This mode may be useful if the vehicle becomes
stuck. This mode may modify TCS and ESC
thresholds for activation, which allows for more
wheel spin than normally allowed.
To enter the “Partial Off” mode, momentarily
push the ESC OFF switch and the ESC OFF
Indicator Light will illuminate. To turn the ESC
on again, momentarily push the ESC OFF switch
and the ESC OFF Indicator Light will turn off.
NOTE:
For vehicles with multiple partial ESC modes,
the push and release of the button will toggle
the ESC modes. Multiple attempts may be
required to return to “ESC On”.
WARNING!
Electronic Stability Control (ESC) cannot
prevent the natural laws of physics from
acting on the vehicle, nor can it increase
the traction afforded by prevailing road
conditions. ESC cannot prevent accidents,
including those resulting from excessive
speed in turns, driving on very slippery
surfaces, or hydroplaning. ESC also cannot
prevent accidents resulting from loss of
vehicle control due to inappropriate driver
input for the conditions. Only a safe, atten
-
tive, and skillful driver can prevent acci -
dents. The capabilities of an ESC equipped
vehicle must never be exploited in a reck -
less or dangerous manner which could
jeopardize the user’s safety or the safety of
others.Vehicle modifications, or failure to properly
maintain your vehicle, may change the
handling characteristics of your vehicle,
and may negatively affect the performance
of the ESC system. Changes to the steering
system, suspension, braking system, tire
type and size or wheel size may adversely
affect ESC performance. Improperly
inflated and unevenly worn tires may also
degrade ESC performance. Any vehicle
modification or poor vehicle maintenance
that reduces the effectiveness of the ESC
system can increase the risk of loss of
vehicle control, vehicle rollover, personal
injury and death.
WARNING! (Continued)
6

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314SAFETY
(Continued)
Full Off — If Equipped
This mode is intended for off-highway or
off-road use only and should not be used on any
public roadways. In this mode, TCS and ESC
features are turned off. To enter the “Full Off”
mode, push and hold the ESC OFF switch for five
seconds while the vehicle is stopped with the
engine running. After five seconds, a chime will
sound, the ESC OFF Indicator Light will
illuminate, and the “ESC OFF” message will
display in the instrument cluster. To turn ESC on
again, momentarily push the ESC OFF switch.NOTE:
System may switch from ESC “Full Off” to
“Partial Off” mode when vehicle exceeds a
predetermined speed. When the vehicle speed
slows below the predetermined speed the
system will return to ESC “Full Off”.
ESC modes may also be affected by drive
modes (if equipped).
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 placed in the ON/RUN 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.
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.
WARNING!
In the ESC “Full Off” mode, the engine
torque reduction and stability features are
disabled. Therefore, enhanced vehicle
stability offered by the ESC system is
unavailable. In an emergency evasive
maneuver, the ESC system will not engage
to assist in maintaining stability. ESC “Full
Off” mode is intended for off-highway or
off-road use only.
The Electronic Stability Control (ESC)
cannot prevent the natural laws of physics
from acting on the vehicle, nor can it
increase the traction afforded by prevailing
road conditions. ESC cannot prevent all
accidents, including those resulting from
excessive speed in turns, driving on very
slippery surfaces, or hydroplaning. ESC also
cannot prevent collisions.
WARNING! (Continued)

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SAFETY315
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.
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 is
placed in the ON/RUN mode.
Each time the ignition is placed in the ON/
RUN mode, 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 Descent Control (HDC) — If Equipped
HDC is intended for low speed off-road driving
while in 4WD Low. HDC maintains vehicle speed
while descending hills during various driving
situations. HDC controls vehicle speed by
actively controlling the brakes.
HDC Has Three States:

1. Off (feature is not enabled and will not activate).

2. Enabled (feature is enabled and ready but activation conditions are not met, or driver
is actively overriding with brake or throttle
application).
3. Active (feature is enabled and actively controlling vehicle speed).
Enabling HDC
HDC is enabled by pushing the HDC switch, but
the following conditions must also be met to
enable HDC:
Driveline is in 4WD Low.
Vehicle speed is below 5 mph (8 km/h).
The parking brake is released.
The driver door is closed. Activating HDC
Once HDC is enabled it will activate
automatically if driven down a grade of
sufficient magnitude. The set speed for HDC is
selectable by the driver, and can be adjusted by
using the gear shift +/-. The following
summarizes the HDC set speeds:
HDC Target Set Speeds
P = No set speed. HDC may be enabled but
will not activate.
R = 0.6 mph (1 km/h)
N = 1.2 mph (2 km/h)
D = 0.6 mph (1 km/h)
1st = 0.6 mph (1 km/h)
2nd = 1.2 mph (2 km/h)
3rd = 1.8 mph (3 km/h)
4th = 2.5 mph (4 km/h)
5th = 3.1 mph (5 km/h)
6th = 3.7 mph (6 km/h)
7th = 4.3 mph (7 km/h)
8th = 5.0 mph (8 km/h)
9th = 5.6 mph (9 km/h) – If Equipped
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SAFETY317
Hill Start Assist (HSA)
HSA is designed to mitigate roll back from a
complete stop while on an incline. If the driver
releases the brake while stopped on an incline,
HSA will continue to hold the brake pressure for
a short period. If the driver does not apply the
throttle before this time expires, the system will
release brake pressure and the vehicle will roll
down the hill as normal.
The following conditions must be met in order
for HSA to activate:
The feature must be enabled.
The vehicle must be stopped.
The parking brake must be off.
The driver door must be closed.
The vehicle must be on a sufficient grade.
The gear selection must match vehicle uphill
direction (i.e., vehicle facing uphill is in
forward gear; vehicle backing uphill is in
REVERSE gear).
HSA will work in REVERSE gear and all
forward gears. The system will not activate if
the transmission is in PARK or NEUTRAL.
Disabling And Enabling HSA
This feature can be turned on or turned off. To
change the current setting, proceed as follows:
If disabling HSA using Uconnect Settings
Úpage 237.
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.WARNING!
There may be situations where the Hill Start
Assist (HSA) will not activate and slight rolling
may occur, such as on minor hills or with a
loaded vehicle, or while pulling a trailer. HSA
is not a substitute for active driving
involvement. It is always the driver’s
responsibility to be attentive to distance to
other vehicles, people, and objects, and most
importantly brake operation to ensure safe
operation of the vehicle under all road
conditions. Your complete attention is always
required while driving to maintain safe control
of your vehicle. Failure to follow these
warnings can result in a collision or serious
personal injury.
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.
6

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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.

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SAFETY319
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.
BSM 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).
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 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 system may also detect a blockage if the
vehicle is operated in areas with extremely low
radar returns such as a desert or parallel to a
large elevation drop.
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 322.

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.
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320SAFETY
Entering From The Side
Vehicles that move into your adjacent lanes
from either side of the vehicle.

Side Monitoring

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.

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