brake light RAM 1500 2021 Service Manual

MULTIMEDIA251
Trailer Brake/Trailer
When the Trailer Brake/Trailer button is pressed on the touchscreen, the system will display settings related to trailer towing.
Audio
When the Audio button is pressed on the touchscreen, the system displays options related to the vehicle’s sound system. These settings can change
the audio location within the vehicle, adjust the bass or treble levels, and auto-play settings from an audio device or smartphone.
Setting Name Description
Trailer Select Select from Trailer 1, Trailer 2, Trailer 3, and Trailer 4. These trailer
designations can be used to save different trailer settings.
Trailer Brake Type This setting will set the system to a specific trailer type. The available
options are “Light Electrics”, “Heavy Electric”, “Light
Electric-Over-Hydraulic”, and “Heavy Electric-Over-Hydraulic”.
Trailer Name This setting will personalize the trailer name depending on the type of
trailer you are hauling. Select the trailer name from the following list:
trailer, boat, car, cargo, dump, equipment, flatbed, gooseneck, horse,
livestock, motorcycle, snowmobile, travel, utility, and 5th wheel.
Setting Name
Description
Balance/Fade This setting will adjust audio levels from specific speakers in the front/
back and left/right of the vehicle. The Speaker icon can be moved to set
audio location.
Equalizer This setting will adjust the “Bass”, “Mid”, and “Treble” ranges of the
audio.
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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.
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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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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.
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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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324SAFETY
Trailer length between 30 ft and 39.5 ft (9 m
to 12 m) — Blind spot zone will be adjusted to
Max distance .
NOTE:
Trailer length is determined within +/- 3 ft (1 m)
of actual length. Trailers that are the same size
as the category limit, 10/20/30 ft (3/6/9 m),
could be subject to being placed in the category
above or below the correct one.
Trailer Merge Warning
Trailer Merge Warning is the extension of the
blind spot function to cover the length of the
trailer, plus a safety margin, to warn the driver
when there is a vehicle in the adjacent lane. The
driver is alerted by the illumination of the BSM
warning light located in the outside mirror on
the side the other vehicle is detected on. In
addition, an audible (chime) alert will be heard
and radio volume will be reduced Ú page 322.
NOTE:
The Trailer Merge Alert system DOES NOT
alert the driver about rapidly approaching
vehicles that are outside the detection zones.
The Blind Spot Monitoring (BSM) system may
experience drop outs (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).
Crowded areas such as parking lots, neigh
-
borhoods, etc. may lead to an increased
amount of false alerts. This is normal opera -
tion.
FORWARD COLLISION WARNING (FCW)
W
ITH MITIGATION — IF EQUIPPED
FCW with Mitigation provides the driver with
audible warnings, visual warnings (within the
instrument cluster display), and may apply a
brake jerk to warn the driver when it detects a potential frontal collision. The warnings and
limited braking are intended to provide the
driver with enough time to react, avoid or
mitigate the potential collision.
NOTE:
FCW monitors the information from the forward
looking sensors as well as the Electronic Brake
Controller (EBC), to calculate the probability of a
forward collision. When the system determines
that a forward collision is probable, the driver
will be provided with audible and visual warn-
ings as well as a possible brake jerk warning.
If the driver does not take action based upon
these progressive warnings, then the system
will provide a limited level of active braking to
help slow the vehicle and mitigate the potential
forward collision. If the driver reacts to the warn
-
ings by braking and the system determines that
the driver intends to avoid the collision by
braking but has not applied sufficient brake
force, the system will compensate and provide
additional brake force as required.
If a FCW with Mitigation event begins at a speed
below 32 mph (52 km/h), the system may
provide the maximum braking possible to miti -
gate the potential forward collision. If the
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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SAFETY327
Pedestrian Emergency Braking (PEB) — If
Equipped
PEB is a subsystem of the FCW system that
provides the driver with audible and visual
warnings in the instrument cluster display, and
may apply automatic braking when it detects a
potential frontal collision with a pedestrian.
If a PEB event begins at a speed below 37 mph
(60 km/h), the system may provide braking to
mitigate the potential collision with a
pedestrian. If the PEB event stops the vehicle
completely, the system will hold the vehicle at a
standstill for two seconds and then release the
brakes. When the system determines a collision
with the pedestrian in front of you is no longer
probable, the warning message will be
deactivated.
The minimum speed for PEB activation is 3 mph
(5 km/h). Turning PEB On Or Off
NOTE:
The default status of PEB is “On.” This allows
the system to warn you of a possible frontal
collision with the pedestrian.
The PEB button is located in the Uconnect
display in the controls settings Ú
page 237.
To turn the PEB system off, push the Pedestrian
Emergency Braking button once.
To turn the PEB system back on, push the
Pedestrian Emergency Braking button again.
Changing the PEB status to “Off” deactivates
the system, so no warning or active braking will
be available in case of a possible frontal
collision with the pedestrian. NOTE:
The PEB system will NOT retain the last setting
selected by the driver after ignition shut down.
The system will reset to the default setting when
the vehicle is restarted.
TIRE PRESSURE MONITORING SYSTEM
(TPMS)
TPMS will warn the driver of a low tire pressure
based on the vehicle recommended cold
placard pressure.
NOTE:
The TPMS Warning Light will illuminate in the
instrument cluster and a chime will sound when
tire pressure is low in one or more of the four
active road tires. In addition, the instrument
cluster will display a graphic showing the pres -
sure values of each tire with the low tire pres -
sure values in a different color, or the Uconnect
radio will display a TPMS message; when this
occurs you must increase the tire pressure to
the recommended cold placard pressure in
order for the TPMS Warning Light to turn off.
The tire pressure will vary with temperature by
about 1 psi (7 kPa) for every 12°F (6.5°C). This
means that when the outside temperature
decreases, the tire pressure will decrease. Tire
WARNING!
Pedestrian Emergency Braking (PEB) is not
intended to avoid a collision on its own, nor
can PEB detect every type of potential colli -
sion with a pedestrian. The driver has the
responsibility to avoid a collision by con -
trolling the vehicle via braking and steering.
Failure to follow this warning could lead to
serious injury or death.
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SAFETY353
eye irritation, rinse the area with cool water.
For nose or throat irritation, move to fresh air.
If the irritation continues, see your doctor. If
these particles settle on your clothing, follow
the garment manufacturer’s instructions for
cleaning.
Do not drive your vehicle after the air bags have
deployed. If you are involved in another
collision, the air bags will not be in place to
protect you.
NOTE:
Air bag covers may not be obvious in the inte -
rior trim, but they will open during air bag
deployment.
After any collision, the vehicle should be
taken to an authorized dealer immediately.
Enhanced Accident Response System
In the event of an impact, if the communication
network remains intact, and the power remains
intact, depending on the nature of the event,
the Occupant Restraint Controller (ORC) will
determine whether to have the Enhanced
Accident Response System perform the
following functions:
Cut off fuel to the engine (if equipped)
Cut off battery power to the electric motor (if
equipped)
Flash hazard lights as long as the battery has
power
Turn on the interior lights, which remain on
as long as the battery has power or for
15 minutes from the intervention of the
Enhanced Accident Response System
Unlock the power door locks
Your vehicle may also be designed to perform
any of these other functions in response to the
Enhanced Accident Response System:
Turn off the Fuel Filter Heater, Turn off the
HVAC Blower Motor, Close the HVAC Circula -
tion Door
Cut off battery power to the:
Engine
Electric Motor (if equipped)
Electric power steering
Brake booster
Electric park brake
Automatic transmission gear selector
Horn
Front wiper
Headlamp washer pump
NOTE:
After an accident, remember to cycle the igni -
tion to the STOP (OFF/LOCK) position and
remove the key from the ignition switch to avoid
draining the battery. Carefully check the vehicle
for fuel leaks in the engine compartment and on
the ground near the engine compartment and
fuel tank before resetting the system and
starting the engine. If there are no fuel leaks or
damage to the vehicle electrical devices (e.g.
headlights) after an accident, reset the system
by following the procedure described below. If
you have any doubt, contact an authorized
dealer.
WARNING!
Deployed air bags and seat belt
pretensioners cannot protect you in another
collision. Have the air bags, seat belt
pretensioners, and the seat belt retractor
assemblies replaced by an authorized dealer
immediately. Also, have the Occupant
Restraint Controller System serviced as well.
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