traction control JEEP CHEROKEE TRAILHAWK 2018 Owners Manual

WARNING!(Continued)
•The capabilities of an ABS equipped vehicle must
never be exploited in a reckless or dangerous manner
that could jeopardize the user ’s safety or the safety of
others.
ABS is designed to function with the OEM tires. Modifica-
tion may result in degraded ABS performance.
Anti-Lock Brake Warning Light
The yellow “Anti-Lock Brake Warning Light” will turn on
when the ignition is turned to the ON/RUN mode and
may stay on for as long as four seconds.
If the “Anti-Lock Brake Warning Light” remains on or
comes on while driving, it indicates that the anti-lock
portion of the brake system is not functioning and that
service is required. However, the conventional brake sys-
tem will continue to operate normally if the “Anti-Lock
Brake Warning Light” is on.
If the “Anti-Lock Brake Warning Light” is on, the brake
system should be serviced as soon as possible to restore
the benefits of anti-lock brakes. If the “Anti-Lock Brake Warning Light” does not come on when the ignition is
turned to the ON/RUN mode, have the light repaired as
soon as possible.
Electronic Brake Control System
Your vehicle is equipped with an advanced Electronic
Brake Control system (EBC). This system includes Elec-
tronic Brake Force Distribution (EBD), Anti-Lock Brake
System (ABS), Brake Assist System (BAS), Hill Start Assist
(HSA), Traction Control System (TCS), Electronic Stability
Control (ESC), and Electronic Roll Mitigation (ERM). These
systems work together to enhance both vehicle stability
and control in various driving conditions.
Your vehicle may also be equipped with Trailer Sway
Control (TSC), Ready Alert Braking (RAB), Rain Brake
Support (RBS), Dynamic Steering Torque (DST), Hill De-
scent Control (HDC), and Selec-Speed Control (SSC).
Electronic Brake Force Distribution (EBD)
This function manages the distribution of the braking
torque between the front and rear axles by limiting braking
pressure to the rear axle. This is done to prevent overslip of
the rear wheels to avoid vehicle instability, and to prevent
the rear axle from entering ABS before the front axle.
5
SAFETY 151

WARNING!(Continued)
•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 all
accidents, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. ESC also cannot prevent collisions.
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 is turned to the ON mode.
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 an 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 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.
NOTE:
•
The “ESC Activation/Malfunction Indicator Light” and
the “ESC OFF Indicator Light” come on momentarily
each time the ignition is turned ON.
• Each time the ignition is turned ON, the ESC system will
be on even if it was turned off previously.
• 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
customer has elected to have the Electronic Sta-
bility Control (ESC) in a reduced mode.

(Trailhawk only): Avoid driving in standing water deeper
than 19 inches (48 cm), and reduce speed appropriately to
minimize wave effects. Maximum speed in 19 inches (48
cm) of water is less than 5 mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine, transmission, Power Transfer
Unit, and Rear Drive Module) to assure they have not been
contaminated. Contaminated fluids and lubricants (milky,
foamy in appearance) should be flushed/changed as soon
as possible to prevent component damage.
Driving In Snow, Mud And Sand
In heavy snow, when pulling a load, or for additional
control at slower speeds, shift the transmission to a low
gear and shift the 4WD system to the appropriate terrain
mode, using 4WD LOW if necessary. Refer to “Four-Wheel
Drive Operation” in “Starting And Operating” for further
information. Do not shift to a lower gear than necessary to
maintain headway. Over-revving the engine can spin the
wheels and traction will be lost.
Avoid abrupt downshifts on icy or slippery roads because
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 4WD System to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
NOTE: Brakes should be applied at increased slippage, but
before coming to a stop to avoid digging into the loose
surface and rendering the operator of the vehicle stuck/
immobile.
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 brakes. Once stopped, shift to
REVERSE. Back slowly down the hill allowing the com-
pression 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!(Continued)
to turn around. To do so may result in tipping and
rolling the vehicle. Always back straight down a hill in
REVERSE gear carefully. Never back down a hill in
NEUTRAL using only the brake.
NOTE: Remember, never drive diagonally across a hill -
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 headway by turning
the front wheels slowly left and right. This may provide a
fresh “bite” into the surface and may provide traction to
complete the climb.
Traction Downhill
Shift the transmission into a low gear and the 4WD System
to 4WD LOW range or Select Hill Descent Control if
equipped (refer to Safety Featuresin the “Safety” section
for further information). Let the vehicle go slowly down
the hill with all four wheels turning against engine com-
pression 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 transmission
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.
•
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.
6
STARTING AND OPERATING 367

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 manu-
facturer in each category is shown on the sidewall of the
tires on your vehicle.
All passenger vehicle 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 controlledconditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance.