2015 JEEP CHEROKEE traction control

ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system commonly referred to as ESC. This
system includes Anti-Lock Brake System (ABS), Traction
Control System (TCS), Brake Assist System (BAS), Hill
Start Assist (HSA), Electronic Roll Mitigation (ERM), and
Electronic Stability Control (ESC). These systems work
together to enhance both vehicle stability and control in
various driving conditions.
Your vehicle is also equipped with Trailer Sway Control
(TSC), Ready Alert Braking (RAB) and Rain Brake Sup-
port (RBS). Further, all vehicles equipped with a two-
speed power transfer unit have Hill Descent Control
(HDC) and some vehicles may also be equipped with
Selec Speed Control (SSC).
Anti-Lock Brake System
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.
The ABS conducts a low-speed self-test at about 12 mph
(20 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.
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•Do not “ride” the brakes by resting your foot on the
pedal. This could overheat the brakes and result in
unpredictable braking action, longer stopping dis-
tances, or brake damage.
•When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control.
Avoid repeated heavy braking by downshifting the
transmission or locking out overdrive whenever pos-
sible.
•Engines may idle at higher speeds during warm-up,
which could cause rear wheels to spin and result in
loss of vehicle control. Be especially careful while
driving on slippery roads, in close-quarter maneuver-
ing, parking, or stopping.
•Do not drive too fast for road conditions, especially
when roads are wet or slushy. A wedge of water can
build up between the tire tread and the road. This
hydroplaning action can cause loss of traction, braking
ability, and control.
•After going through deep water or a car wash, brakes
may become wet, resulting in decreased performance
and unpredictable braking action. Dry the brakes by
gentle, intermittent pedal action while driving at very
slow speeds.
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
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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
or the “Full Off” mode. 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
quickly results in the best BAS assistance. To receive the
benefit of the system, you must apply continuous brak-
ing 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.
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, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. 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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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 will start to flash as soon
as the tires lose traction and 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!
The Electronic Stability Control (ESC) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. ESC cannot prevent col-
lisions, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. ESC also cannot prevent collisions
resulting from loss of vehicle control due to inappro-
priate driver input for the conditions. Only a safe,
attentive, and skillful driver can prevent collisions.
The capabilities 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.
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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.
NOTE:To improve the vehicle’s traction when driving
with snow chains, or when starting off in deep snow,
sand, or gravel, it may be desirable to switch to the
“Partial Off” mode by momentarily pressing the “ESC
Off” button. Once the situation requiring “Partial Off”
mode is overcome, turn ESC back on by momentarily
pressing the “ESC Off” button. This may be done while
the vehicle is in motion.
Full Off — Four-Wheel Drive Vehicles In 4WD High
And 4WD Low Range
The “Full Off” mode is intended for off-highway and
off-road use when ESC stability features could inhibit
vehicle maneuverability due to trail conditions.
The “ESC Off” button is located in the lower switch bank
above the climate control panel. To enter “Full Off”
mode, press and hold the “ESC Off” button for five
seconds while the vehicle is stopped with the engine
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WARNING!(Continued)
•Never use a tire with a smaller load index or
capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have a collision.
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body
clearance. Follow these recommendations to guard
against damage.
•Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer
•Use on Front Tires Only
•Due to limited clearance, the following traction de-
vices are recommended:
Front Wheel Drive (FWD) Models
•Original equipment 225/60R17 and 225/55R18 tire
sizes are not chainable.
•The use of 7mm snow chains is permitted with the use
of 215/60R17 tires on size 17 x 7.0 ET41 wheels.
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Four Wheel Drive (4WD) Non-Trailhawk Models with-
out a Two-Speed Power Takeoff Unit
•Original equipment 225/65R17 and 225/60R18 tire
sizes are not chainable.
•The use of 9mm snow chains is permitted with the use
of 215/60R17 tires on size 17 x 7.0 ET41 wheels.
Four Wheel Drive (4WD) Non-Trailhawk Models with a
Two-Speed Power Takeoff Unit
•The use of 7mm snow chains is permitted with 225/
65R17 and 225/60R18 tires.
Four Wheel Drive (4WD) Trailhawk Models
•The use of 9mm snow chains is permitted with the use
of 225/65R17 tires on size 17 x 7.5 ET31 wheels.
CAUTION!
•Use on Front Tires Only
•Damage to Front Wheel Drive (FWD) Models may
result if tire chains or traction devices are used with
original equipment size tires.
•Damage to Four Wheel Drive (4WD) Models with-
out a Two-Speed Power Takeoff Unit may result if
tire chains or traction devices are used with origi-
nal equipment size tires.
•Damage to Four Wheel Drive (4WD) Trailhawk
Models may result if tire chains or traction devices
are used with original equipment size tires.
WARNING!
Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
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•1–800–890–4038 (U.S.)
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Or
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DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES
The following tire grading categories were established by
the National Highway Traffic Safety Administration. The
specific grade rating assigned by the tire’s manufacturer
in each category is shown on the sidewall of the tires on
your vehicle.
All passenger car tires must conform to Federal safety
requirements in addition to these grades.
Treadwear
The Treadwear grade is a comparative rating, based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and one-half
times as well on the government course as a tire graded
100. The relative performance of tires depends upon the
actual conditions of their use, however, and may depart
significantly from the norm due to variations in driving
habits, service practices, and differences in road charac-
teristics and climate.
Traction Grades
The Traction grades, from highest to lowest, are AA, A, B,
and C. These grades represent the tire’s ability to stop on
wet pavement, as measured under controlled conditions
on specified government test surfaces of asphalt and9
IF YOU NEED CONSUMER ASSISTANCE 745