2015 Ram 1500 brakes

with a separate computer to modulate hydraulic pressure
to prevent wheel lockup and help avoid skidding on
slippery surfaces.
The system’s pump motor runs during an ABS stop to
provide regulated hydraulic pressure. The pump motor
makes a low humming noise during operation. This is
normal.
The ABS conducts a low-speed selftest at about 10 mph
(16 km/h). If you have your foot lightly on the brake
while this test is occurring, you may feel slight pedal
movement. The movement can be more apparent on ice
and snow. This is normal.
When you are in a severe braking condition involving
use of the ABS, you will experience some pedal drop as
the vehicle comes to a complete stop. This is the result of
the system reverting to the base brake system and is
normal.
Engagement of the ABS may be accompanied by a
pulsing sensation. You may also hear a clicking noise.
These occurrences are normal, and indicate that the
system is functioning.
WARNING!
•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 Anti-Lock Brake System (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.
(Continued)
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WARNING!(Continued)
•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 which could jeopardize the user’s safety or
the safety of others.
ABS Warning Light
The ABS includes an amber warning light. When the light
is illuminated, the ABS is not functioning. The system
reverts to standard, non-anti-lock brakes.
Traction Control System (TCS)
The 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 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 TCS and ESC are in
the “Partial Off” mode. Refer to “Electronic Stability
Control (ESC)” in this section of this manual. This brake
pressure modulation transfers drive torque from slipping
to non-slipping wheels to provide optimal forward trac-
tion.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
BAS detects an emergency braking situation by sensing
the rate and amount of brake application and then
applies optimum pressure to the brakes. The system
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applies optimum pressure to the brakes in emergency
braking conditions. This can help reduce braking dis-
tances. The BAS complements the ABS. Applying the
brakes very quickly results in the best BAS assistance. To
receive the benefit of BAS, you must apply continuous
braking pressure during the stopping sequence. Do not
reduce brake pedal pressure unless braking is no longer
desired.
Once the brake pedal is released, the BAS is deactivated.
WARNING!
•The BAS cannot prevent the natural laws of phys-
ics from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded.
(Continued)
WARNING!(Continued)
•The BAS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, 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.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver in
launching a vehicle on an incline. HSA will maintain the
level of brake pressure the driver inputs for a short
duration once the driver takes his foot off of the brake
pedal. If the driver does not apply the throttle during this
short duration, the system will release brake pressure
and the vehicle will roll down the incline. The system will
release brake pressure in proportion to the amount of
throttle applied.
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Towing And Hauling With HSA
The HSA system does not know if your vehicle is loaded
or towing a trailer unless the TOW/HAUL switch, lo-
cated on the center stack, is selected. When activated, the
“TOW/HAUL Indicator Light” will illuminate in the
instrument cluster. Refer to “Automatic Transmission” in
“Starting and Operating” for further information. In
order to accommodate the extra weight entailed under
towing and hauling conditions and to increase driver
comfort while launching on a hill, the system recognizes
when the TOW/HAUL switch is activated and compen-
sates by releasing brake pressure at a slower rate while
throttle is applied in order to prevent the vehicle from
rolling down the hill.
WARNING!
•If you use a trailer brake controller with your
trailer, your trailer brakes may be activated and
deactivated with the brake switch. If so, when the
brake pedal is released, there may not be enough
brake pressure to hold the vehicle and trailer on a
hill and this could cause a collision with another
vehicle or object behind you. In order to avoid
rolling down the incline while resuming accelera-
tion, manually activate the trailer brake or apply
more vehicle brake pressure prior to releasing the
brake pedal. Always remember the driver is re-
sponsible for braking the vehicle.
(Continued)
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NOTE:
•The “ESC Activation/Malfunction Indicator Light”
and the “ESC OFF Indicator Light” come on momen-
tarily each time the ignition switch is turned ON.
•Each time the ignition is turned ON, the ESC system
will be ON even if it was turned off previously. Except
for when the vehicle is started while in 4WD Low
Range.
•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.
The “ESC OFF Indicator Light” indicates the
Electronic Stability Control (ESC) is in#ESC
Partial Off#or#ESC Full Off#.
Trailer Sway Control (TSC)
The TSC system uses sensors in the vehicle to recognize
an excessively swaying trailer and will take the appro-
priate 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.
TSC will become active automatically once an excessively
swaying trailer is recognized. No driver action is re-
quired to activate. Note that TSC cannot stop all trailers
from swaying. Always use caution when towing a trailer
and follow the trailer tongue weight recommendations.
Refer to “Trailer Towing” in “Starting and Operating” for
further information. 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 “ESC Partial Off” or “ESC Full Off”
modes.
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TSC is only active in the default “ESC On” mode. TSC
can be disabled by pressing the “ESC Off” switch and
entering “ESC Partial Off” mode. It is not active in the
“ESC Partial Off” or “ESC Full Off” modes. Refer to the
ESC portion of this section for an explanation of the
different ESC operating modes.
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.
Hill Descent Control (HDC) — If Equipped
HDC is intended for low speed off road driving while in
4WD Low Range. 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 pressing the HDC switch, but the
following conditions must also be met to enable HDC:
•Driveline is in 4WD Low Range.
•Vehicle speed is below 5 mph (8 Km/h).
•Parking brake is released.
•Driver door is closed.
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Feedback to the driver:
The instrument cluster has a HDC icon and a HDC
switch which has an LED which offers feedback to the
driver about the state HDC is in.
•While HDC is Enabled or Active the gear position
typically associated with ERS manual mode will indi-
cate target set speed not the top gear limit which is
typical of ERS manual mode.
•The cluster icon and switch lamp will illuminate and
remain on solid when HDC is enabled or activated.
This is the normal operating condition for HDC.
•The cluster icon and switch lamp will flash for several
seconds then extinguish when the driver presses the
HDC switch but enable conditions are not met.
•The cluster icon and switch lamp will flash for several
seconds then extinguish when HDC deactivates due to
excess speed.
•The cluster icon and switch lamp will flash when HDC
deactivates due to overheated brakes. The flashing will
stop and HDC will activate again once the brakes have
cooled sufficiently.
WARNING!
HDC is only intended to assist the driver in control-
ling vehicle speed when descending hills. The driver
must remain attentive to the driving conditions and
is responsible for maintaining a safe vehicle speed.
596 STARTING AND OPERATING

items down low and be sure that the weight is distributed
equally. Stow all loose items securely before driving.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
CAUTION!
Do not load your vehicle any heavier than the GVWR
or the maximum front and rear GAWR. If you do,
parts on your vehicle can break, or it can change the
way your vehicle handles. This could cause you to
lose control. Also overloading can shorten the life of
your vehicle.
TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer, carefully
review this information to tow your load as efficiently
and safely as possible.
To maintain the New Vehicle Limited Warranty coverage,
follow the requirements and recommendations in this
manual concerning vehicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
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