2015 JEEP GRAND CHEROKEE traction control

Avoid abrupt downshifts on icy or slippery roads, be-
cause engine braking may cause skidding and loss of
control.
Hill Climbing
NOTE:Before attempting to climb a hill, determine the
conditions at the crest and/or on the other side.
Before climbing a steep hill,shift the transmission to a
lower gear and shift the transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
If you stall or begin to lose forward motionwhile
climbing a steep hill, allow your vehicle to come to a stop
and immediately apply the brakes. Restart the engine,
and shift into REVERSE. Back slowly down the hill,
allowing the compression braking of the engine to help
regulate your speed. If the brakes are required to control
vehicle speed, apply them lightly and avoid locking or
skidding the tires.
WARNING!
If the engine stalls, you lose forward motion, 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. Always back care-
fully straight down a hill in REVERSE gear. Never
back down a hill in NEUTRAL using only the brake.
Remember, never drive diagonally across a hill always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain forward motion
by turning the front wheels slowly. This may provide a
fresh “bite” into the surface and will usually provide
traction to complete the climb.
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Traction Downhill
When descending mountains or hills, use Hill Descent or
Selec-Speed Control to avoid repeated heavy braking.
If not equipped with Hill Descent or Selec-Speed Control
use the following procedure:
Shift the transmission into a low gear, and the transfer
case into 4WD LOW range. Let the vehicle go slowly
down the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
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In the event power assist is lost for any reason (i.e.,
repeated brake applications with the engine off) the
brakes will still function. However, 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 the Anti-Lock Brake
System (ABS), Traction Control System (TCS), Brake
Assist System (BAS), Electronic Roll Mitigation (ERM),
and Electronic Stability Control (ESC). All five of these
systems work together to enhance vehicle stability and
control in various driving conditions.
Also, your vehicle may be equipped with Trailer Sway
Control (TSC), Hill Start Assist (HSA), Ready Alert
Braking (RAB), Rain Brake Support (RBS) and, if it has
four-wheel drive with the MP 3023 two-speed transfer
case, Hill Descent Control (HDC), Selec Speed Control
(SSC).
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.
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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
ESC system is in the “Partial Off” mode. Refer to “Elec-
tronic 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!
Many factors, such as vehicle loading, road condi-
tions, and driving conditions, influence the chance
that wheel lift or rollover may occur. ERM cannot
prevent all wheel lift or rollovers, especially those
that involve leaving the roadway or striking objects
or other vehicles. The capabilities of an ERM-
equipped vehicle must never be exploited in a reck-
less 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. ESC cor-
rects for oversteering or understeering of the vehicle by
applying the brake of the appropriate wheel to assist in
counteracting the oversteer or understeer condition. En-
gine 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 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
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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
(Continued)
WARNING!(Continued)
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 two available operating modes in
4WD HIGH range and two-wheel drive vehicles, and one
operating mode in 4WD LOW range.
High Range (Four-Wheel Drive Models) Or
Two-Wheel Drive Models
On
This is the normal operating mode for ESC in 4WD HIGH
range and in two-wheel drive vehicles. Whenever the
vehicle is started or the transfer case (if equipped) is
shifted from 4WD LOW range or NEUTRAL back to
4WD HIGH range, the ESC system will be in this “On”
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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.
NOTE:
•The “ESC Off Indicator Light” and the “ESC
Activation/Malfunction Indicator Light” come on mo-
mentarily each time the ignition switch is turned to the
ON/RUN position.
•Each time the ignition is cycled to the ON/RUN
position, the ESC system will be ON even if it was
cycled off previously, except for when the vehicle is
started while in 4L 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 partially
off or full off.
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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.
•Install on Rear Tires Only
•Due to limited clearance, Thule XG-12 Pro or equiva-
lent is recommended on P245/70/R17, P265/60R18 or
265/50R20 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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