2021 RAM 1500 traction control

310 (Continued)
SAFETY
SAFETY FEATURES
ANTI-LOCK BRAKE SYSTEM (ABS)
The ABS provides increased vehicle stability
and brake performance under most braking
conditions. The system automatically prevents
wheel lock, and enhances vehicle control during
braking.
The ABS performs a self-check cycle to ensure
that the ABS is working properly each time the
vehicle is started and driven. During this
self-check, you may hear a slight clicking sound
as well as some related motor noises.
The ABS is activated during braking when the
system detects one or more wheels are
beginning to lock. Road conditions such as ice,
snow, gravel, bumps, railroad tracks, loose
debris, or panic stops may increase the
likelihood of ABS activation(s).You also may experience the following normal
characteristics when ABS activates:
ABS motor noise or clicking sounds (you may
continue to hear for a short time after the
stop)
Brake pedal pulsations
A slight drop of the brake pedal at the end of
the stop
The ABS is designed to function with the
Original Equipment Manufacturer (OEM) tires.
Modification may result in degraded ABS
performance.
WARNING!
The ABS contains sophisticated electronic
equipment that may be susceptible to inter -
ference caused by improperly installed or
high output radio transmitting equipment.
This interference can cause possible loss of
anti-lock braking capability. Installation of
such equipment should be performed by
qualified professionals.
Pumping of the Anti-Lock Brakes will
diminish their effectiveness and may lead
to a collision. Pumping makes the stopping
distance longer. Just press firmly on your
brake pedal when you need to slow down or
stop.
The ABS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking or steering efficiency
beyond that afforded by the condition of the
vehicle brakes and tires or the traction
afforded.
The ABS cannot prevent collisions,
including those resulting from excessive
speed in turns, following another vehicle
too closely, or hydroplaning.
The capabilities of an ABS equipped vehicle
must never be exploited in a reckless or
dangerous manner that could jeopardize
the user’s safety or the safety of others.
WARNING! (Continued)

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SAFETY311
Anti-Lock Brake System (ABS) Warning
Light
The yellow ABS Warning Light will turn on when
the ignition is placed in the ON/RUN mode and
may stay on for as long as four seconds.
If the ABS Warning Light remains on or comes
on while driving, it indicates that the anti-lock
portion of the brake system is not functioning
and that service is required. However, the
conventional brake system will continue to
operate normally if the ABS Warning Light is on.
If the ABS Warning Light is on, the brake system
should be serviced as soon as possible to
restore the benefits of anti-lock brakes. If the
ABS Warning Light does not come on when the
ignition is placed in the ON/RUN mode, have
the light repaired as soon as possible.
ELECTRONIC BRAKE CONTROL (EBC)
S
YSTEM
Your vehicle is equipped with an advanced
Electronic Brake Control (EBC) system. This
system includes Anti-Lock Brake System (ABS),
Brake Assist System (BAS), Electronic Brake
Force Distribution (EBD), Electronic Roll
Mitigation (ERM), Electronic Stability Control
(ESC), Hill Start Assist (HSA), and Traction Control System (TCS). These systems work
together to enhance both vehicle stability and
control in various driving conditions.
Your vehicle may also be equipped with Trailer
Sway Control (TSC) and Hill Descent Control
(HDC).
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.
Brake System Warning Light
The red Brake System Warning Light will turn on
when the ignition is placed in the ON/RUN
mode and may stay on for as long as four
seconds.
If the Brake System Warning Light remains on or
comes on while driving, it indicates that the
brake system is not functioning properly and
that immediate service is required. If the Brake
System Warning Light does not come on when
the ignition is placed in the ON/RUN mode,
have the light repaired as soon as possible.
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.
6

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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
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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454SERVICING AND MAINTENANCE
TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between different all season
tires. All season tires can be identified by the
M+S, M&S, M/S or MS designation on the tire
sidewall. Use all season tires only in sets of four;
failure to do so may adversely affect the safety
and handling of your vehicle.
Summer Or Three Season Tires — If
Equipped
Summer tires provide traction in both wet and
dry conditions, and are not intended to be
driven in snow or on ice. If your vehicle is
equipped with Summer tires, be aware these
tires are not designed for Winter or cold driving
conditions. Install Winter tires on your vehicle
when ambient temperatures are less than 40°F
(5°C) or if roads are covered with ice or snow.
For more information, contact an authorized
dealer.
Summer tires do not contain the all season
designation or mountain/snowflake symbol on
the tire sidewall. Use Summer tires only in sets
of four; failure to do so may adversely affect the
safety and handling of your vehicle.
Snow Tires
Some areas of the country require the use of
snow tires during the Winter. Snow tires can be
identified by a “mountain/snowflake” symbol
on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the
original equipment tires. Use snow
tires only in sets of four; failure to do
so may adversely affect the safety and handling
of your vehicle.
Snow tires generally have lower speed ratings
than what was originally equipped with your
vehicle and should not be operated at
sustained speeds over 75 mph (120 km/h). For
speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer
for recommended safe operating speeds,
loading and cold tire inflation pressures.
While studded tires improve performance on
ice, skid and traction capability on wet or dry
surfaces may be poorer than that of
non-studded tires. Some states prohibit
studded tires; therefore, local laws should be
checked before using these tire types.Failure to equip your vehicle with tires
having adequate speed capability can
result in sudden tire failure and loss of
vehicle control.
CAUTION!
Replacing original tires with tires of a
different size may result in false speedometer
and odometer readings.
WARNING! (Continued)
WARNING!
Do not use Summer tires in snow/ice
conditions. You could lose vehicle control,
resulting in severe injury or death. Driving too
fast for conditions also creates the possibility
of loss of vehicle control.

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SERVICING AND MAINTENANCE459
(Continued)
(Continued)
4x4 (4WD)
Trim Level Axle
Tire/Wheel Size Snow Traction Device
(maximum projection beyond tire profile or equivalent)
Tradesman
Bighorn Lonestar Laramie Rear
275/65R18
275/55/R20 S Class
Longhorn Sport
Limited Rear
275/55R20 S Class
REBEL Not Chainable
WARNING!
Using tires of different size and type (M+S,
Snow) between front and rear axles can
cause unpredictable handling. You could lose
control and have a collision.
CAUTION!
To avoid damage to your vehicle or tires,
observe the following precautions:
Because of restricted traction device clear-
ance between tires and other suspension
components, it is important that only trac-
tion devices in good condition are used.
Broken devices can cause serious damage.
Stop the vehicle immediately if noise
occurs that could indicate device breakage.
Remove the damaged parts of the device
before further use.
Install device as tightly as possible and
then retighten after driving about ½ mile
(0.8 km). Autosock traction devices do not
require retightening.
Do not exceed 30 mph (48 km/h).
Drive cautiously and avoid severe turns and
large bumps, especially with a loaded
vehicle.
Do not drive for a prolonged period on dry
pavement.
CAUTION! (Continued)
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