2015 JEEP WRANGLER traction control

and maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a fresh#bite#into the surface and will usually
provide enough traction to complete the climb. If you do
not make it to the top, place the vehicle in REVERSE and
back straight down the grade using engine resistance
along with the vehicle brakes.
WARNING!
Never attempt to climb a hill at an angle or turn
around on a steep grade. Driving across an incline
increases the risk of a rollover, which may result in
severe injury.
Driving Downhill
Before driving down a steep hill, you need to determine
if it is too steep for a safe descent. What is the surface
traction? Is the grade too steep to maintain a slow,
controlled descent? Are there obstacles? Is it a straight
descent? Is there plenty of distance at the base of the hill
to regain control if the vehicle descends to fast? If you feel
confident in your ability to proceed, then make sure you
are in 4L (Low) and proceed with caution. Allow engine
braking to control the descent and apply your brakes, if
necessary, but do not allow the tires to lock.
WARNING!
Do not descend a steep grade in NEUTRAL. Use
vehicle brakes in conjunction with engine braking.
Descending a grade too fast could cause you to lose
control and be seriously injured or killed.
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Driving Across An Incline
If at all possible, avoid driving across an incline. If it is
necessary, know your vehicle’s abilities. Driving across
an incline places more weight on the downhill wheels,
which increases the possibilities of a downhill slide or
rollover. Make sure the surface has good traction with
firm and stable soils. If possible, transverse the incline at
an angle heading slightly up or down.
WARNING!
Driving across an incline increases the risk of a
rollover , which may result in severe injury.
If You Stall Or Begin To Lose Headway
If you stall or begin to lose headway while climbing a
steep hill, allow your vehicle to come to a stop and
immediately apply the brake. Restart the engine and shift
into REVERSE. Back slowly down the hill allowing
engine braking to control the descent and apply your
brakes, if necessary, but do not allow the tires to lock.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle, which may result in
severe injury. Always back carefully straight down a
hill in REVERSE. Never back down a hill in NEU-
TRAL using only the vehicle brakes. Never drive
diagonally across a hill, always drive straight up or
down.
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In the event power assist is lost for any reason (for
example, repeated brake applications with the engine
OFF) the brakes will still function. The effort required to
brake the vehicle will be much greater than that required
with the power system operating.
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), Hill Start Assist (HSA), Electronic Roll
Mitigation (ERM), Electronic Stability Control (ESC),
Trailer Sway Control (TSC), and Hill Descent Control
(HDC). All of these systems work together to enhance
vehicle stability and control in various driving condi-
tions, and are commonly referred to as ESC.
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) is designed 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 lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type, and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
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CAUTION!
The Anti-Lock Brake System is subject to possible
detrimental effects of electronic interference caused
by improperly installed aftermarket radios or tele-
phones.
NOTE:During severe braking conditions, a pulsing sen-
sation may occur and a clicking noise will be heard. This
is normal, indicating that the Anti-Lock Brake System is
functioning.
Traction Control System (TCS)
This system 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), functions similar 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 either the “Partial Off” or “Full Off”
modes. Refer to “Electronic Stability Control (ESC)” in
this section for further information.
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 sens-
ing 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
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WARNING!(Continued)
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.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by apply-
ing the brake of the appropriate wheel to assist in
counteracting the over/under steer 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.
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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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.
The ESC system has three available operating modes in
4H range. The system has one operating mode in 4L
range. Two-wheel drive vehicles and four-wheel drive
vehicles in 2H range have two operating modes.
4H Range (4WD Models)
ESC On
This is the normal operating mode for ESC in 4H range.
ESC Partial Off
This mode is entered by momentarily pressing the ESC
OFF switch. When in#ESC Partial Off#mode, the TCS
portion of ESC (except for the limited slip feature de-
scribed in the TCS section), has been disabled and the
#ESC Off Indicator Light#will be illuminated.
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This mode is intended to be used if the vehicle is in deep
snow, sand, or gravel conditions and more wheel spin
than ESC 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 function-
ality 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.
ESC Full Off
This mode is entered by pressing and holding momen-
tarily pressing the ESC OFF switch for five seconds.
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WARNING!
•When in “Partial Off” mode, the TCS functionality
of ESC, (except for the limited slip feature de-
scribed 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 sys-
tem is reduced.
•Trailer Sway Control (TSC) is disabled when the
ESC system is in the%Partial Off%mode.
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 cycled to the ON/
RUN position. It should go out with the engine running.
If the “ESC Activation/Malfunction Indicator Light”
comes on continuously with the engine running, a mal-
function 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 authorized
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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