light Ram 1500 2015 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 steering system. 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 System
(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 various driving conditions,
and are commonly referred to as ESC.
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
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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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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.
(Continued)
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portion 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. All other
stability features of ESC function normally. This mode is
intended to be used if the vehicle is in deep snow, sand,
or gravel conditions and more wheel spin than TCS
would normally allow is required to gain traction. To
turn ESC on again, momentarily press the “ESC Off”
switch. This will restore the normal “ESC On” mode of
operation.
NOTE:To improve the vehicle’s traction when driving
with snow chains or starting off in deep snow, sand or
gravel, it may be desirable to switch to the “ESC Partial
Off” mode by pressing the “ESC Off” switch. Once the
situation requiring ESC to be switched to the “ESC Partial
Off” mode is overcome, turn ESC back on by momen-
tarily pressing the “ESC Off” switch. This may be done
while the vehicle is in motion.
WARNING!
•When in “ESC 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 illumi-
nated. When in “ESC 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%ESC Partial Off%mode.
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All Four-Wheel Drive Vehicles In 4WD AUTO And
4WD LOCK Modes Can Also Choose The
Following ESC Operating Mode. This Is The Only
Selectable ESC Operating Mode in 4WD LOW:
ESC Full Off
This mode is intended for off-road use when ESC stabil-
ity features could inhibit vehicle maneuverability due to
trail conditions. This mode is entered by pressing and
holding the “ESC Off” switch for five seconds when the
vehicle is stopped and the engine is running. After five
seconds, the “ESC Off Indicator Light” will illuminate.
Press and release the trip odometer button located on the
instrument cluster to clear this message.
NOTE:The “ESC OFF” message will display and the
audible chime will sound when the shift lever is placed
into the PARK position from any other position and then
moved out of the PARK position. This will occur even if
the message was previously cleared.
In this mode, ESC and TCS except for the “limited slip”
feature described in the TCS section are turned off until
the vehicle reaches a speed of 40 mph (64 km/h). At
40 mph (64 km/h) the system returns to “ESC Partial
Off” mode, described above. When the vehicle speed
drops below 35 mph (56 km/h) the ESC system reverts
back to#ESC Full Off#. ESC is off at low vehicle speeds so
that it will not interfere with off-road driving but ESC
function returns to provide the stability feature at speeds
above 40 mph (64 km/h). The “ESC Off Indicator Light”
will always be illuminated when ESC is in#ESC Partial
Off#and#ESC Full Off#. To turn ESC on again, momen-
tarily press the “ESC Off” switch. This will restore the
normal “ESC On” mode of operation.
“ESC Full Off” is the only operating mode for ESC in
4WD LOW. Whenever the vehicle is started in 4WD LOW
or the transfer case (if equipped) is shifted from 4WD
LOCK or NEUTRAL, to 4WD LOW, the ESC system will
be in this mode.
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WARNING!
In the%ESC Full Off%mode, the engine torque reduc-
tion and stability features are disabled. Therefore,
the enhanced vehicle stability offered by ESC 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.
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 switch is turned to the ON
position. 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 your autho-
rized dealer as soon as possible to have the problem
diagnosed and corrected.
The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster) 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 ac-
celeration, 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.
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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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TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P (Passenger) — Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
•European — Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letter#P#is absent from this tire
size designation. Example: 215/65R15 96H.
•LT (Light Truck) — Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
1—U.S.DOTSafetyStandardsCode (TIN)4—MaximumLoad
2—SizeDesignation 5—MaximumPressure3 — Service Description 6 — Treadwear, Traction andTemperature Grades
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