2015 Ram 2500 Owner's Manual

BRAKE SYSTEM
If power assist is lost for any reason (for example,
repeated brake applications with the engine off), the
brakes will still function. However, you will experience a
substantial increase in braking effort to stop the vehicle.
If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still func-
tion with some loss of overall braking effectiveness. This
will be evident by increased pedal travel during applica-
tion, greater pedal force required to slow or stop, and
activation of the “Brake Warning Light” and the “ABS
Warning Light” (if equipped) during brake use.
Hydraulic Brake Assist — 2500/3500 Models Only
(Except Power Wagon)
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steeringsystem. You may experience some clicking or hissing
noises from the hydro-boost system during hard braking
conditions.
NOTE:
Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Electronic Roll Mitigation (ERM), Hill
Start Assist (HSA), Electronic Stability Control (ESC),
Trailer Sway Control (TSC) and Hill Decent Control
(HDC [Power Wagon only]). All of the systems work
together to enhance vehicle stability and control in vari-
ous driving conditions, and are commonly referred to as
ESC.
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Anti-Lock Brake System (ABS)
The Four-Wheel Anti-Lock Brake System (ABS) is de-
signed to aid the driver in maintaining vehicle control
under adverse braking conditions. The system operates
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 asthe 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
(Continued)
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WARNING!(Continued)
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 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 system, Brake Limited
Differential (BLD), 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 traction.
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
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applies optimum pressure to the brakes. The system
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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During operation, HSA will activate the brake control
system and a clicking noise may occur. If your foot is on
the brake pedal during operation you may feel a slight
pedal movement. The clicking and pedal movement is
normal and both will stop when HSA becomes inactive.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped
• Vehicle must be on an approximate 7% or greater
incline
• Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in REVERSE gear).
WARNING!
There may be situations on minor hills with a loaded
vehicle or while pulling a trailer where the system
will not activate and slight rolling may occur, which
could cause a collision with another vehicle or object.
Always remember the driver is responsible for brak-
ing the vehicle.
The system will only work if the intended direction of the
vehicle and vehicle gear match. For example, if the
intended direction is forward up a hill and the vehicle is
in DRIVE and the activation criteria are met, HSA will
activate.
The system will work in REVERSE and all forward gears,
and will not activate if the vehicle is placed in NEU-
TRAL.
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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.
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WARNING!(Continued)
•HSA is not a parking brake. If you stop the vehicle
on a hill without putting the transmission in PARK
or using the parking brake, it will roll down the
incline and could collide with another vehicle,
object or person, and cause serious or fatal injury.
Always remember to use the parking brake while
parking on a hill and that the driver is responsible
for braking the vehicle.
HSA Off
HSA is a Customer Programmable Feature in the EVIC/
DID. If you wish to turn off the HSA feature, refer to
“Electronic Vehicle Information Center (EVIC)/Driver
Information Display (DID)” in “Understanding Your
Instrument Panel” for further information.
Electronic Stability Control (ESC)
The ESC system enhances directional control and stabil-
ity of the vehicle under various driving conditions. ESC
corrects for oversteering or understeering of the vehicle
by applying the brake of the appropriate wheel to assist
in counteracting the oversteer or understeer condition.
Engine power may also be reduced to help the vehicle
maintain the desired path.
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 appro-
priate wheel to assist in counteracting the oversteer or
understeer condition.
• 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.
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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, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
and skillful driver can prevent accidents. The capa-
bilities of an ESC equipped vehicle must never be
exploited in a reckless or dangerous manner which
could jeopardize the user ’s safety or the safety of
others.
All Two-Wheel Drive Vehicles And Four-Wheel
Drive Vehicles In 2WD, 4WD AUTO, Or 4WD
LOCK Modes Can Choose The Following ESC
Operating Modes:
ESC On
This is the normal operating mode for ESC in 2WD/4WD
AUTO/4WD LOCK modes and in 2WD vehicles. When-
ever the vehicle is started or the transfer case (if equipped)
is shifted from 4WD LOW or Neutral, back to 4WD LOCK
or 4WD AUTO, the ESC system will be in this mode. This
mode should be used for almost all driving situations. ESC
should only be turned toESC Partial Offor “ESC Full
Off” for specific reasons as noted below.
ESC Partial Off
This mode is entered by momentarily pushing the “ESC
Partial Off” switch. When in Partial Offmode, the TCS
portion of ESC, except for the “limited slip” feature
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