2012 JEEP GRAND CHEROKEE four wheel drive

with air suspension, the level will change to Normal
Ride Height (NRH) if the transfer case is in high range.
The level will change to Off-Road 1 if the transfer case
is in Low range.
•Auto– Fully automatic full time four-wheel drive
operation can be used on and off road. Balances
traction with seamless steering feel to provide im-
proved handling and acceleration over two-wheel
drive vehicles. If equipped with air suspension, the
level will change to NRH.
•Sand/Mud – Off road calibration for use on low
traction surfaces such as mud, sand, or wet grass.
Driveline is maximized for traction. Some binding
may be felt on less forgiving surfaces. The electronic
brake controls are set to limit traction control manage-
ment of throttle and wheel spin. If equipped with air
suspension, the level will change to Off-Road 1.
•Rock – Off-road calibration only available in 4WD
Low range. The vehicle is raised (if equipped with Air
Suspension) for improved ground clearance. Traction
based tuning with improved steer-ability for use on
high traction off-road surfaces. Activate the Hill De-
scent Control for steep downhill control. Use for low
speed obstacles such as large rocks, deep ruts, etc. If
equipped with air suspension, the vehicle level will
change to Off-Road 2. If the Selec-Terrain™ switch is in
ROCK mode, and the transfer case is switched from
4WD Low to 4WD High, the Selec-Terrain™ system
will return to AUTO.
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and/or the flow rate is reduced. If you must cross
flowing water avoid depths in excess of 9 inches (23 cm).
The flowing water can erode the streambed, causing your
vehicle to sink into deeper water. Determine exit point(s)
that are downstream of your entry point to allow for
drifting.
Standing Water
Avoid driving in standing water deeper than 20 inches
(51 cm), and reduce speed appropriately to minimize
wave effects. Maximum speed in 20 inches (51 cm) of
water is less than 5 mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine oil, transmission oil, axle,
transfer case) to assure the fluids have not been contami-
nated. Contaminated fluid (milky, foamy in appearance)
should be flushed/changed as soon as possible to pre-
vent 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 transfer case to 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 forward motion.
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 transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
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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.
Traction Downhill
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.5
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WARNING! (Continued)
•Be sure the parking brake is fully disengaged
before driving; failure to do so can lead to brake
failure and a collision.
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also be certain to leave the transmission
in PARK. Failure to do so may allow the vehicle to
roll and cause damage or injury.
CAUTION!
If the “Brake Warning Light” remains on with the
parking brake released, a brake system malfunction
is indicated. Have the brake system serviced by an
authorized dealer immediately.
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 is equipped with Trailer Sway Control
(TSC), Hill Start Assist (HSA), Brake Lock Differential
(BLD), Ready Alert Braking, Rain Brake Support and, if it
has four-wheel drive with the MP 3023 two-speed trans-
fer case, Hill Descent Control (HDC).
Anti-Lock Brake System (ABS)
This system aids the driver in maintaining vehicle control
under adverse braking conditions. The system controls
hydraulic brake pressure to prevent wheel lock-up and
help avoid skidding on slippery surfaces during braking.
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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. 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.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”
mode. This mode should be used for most driving
situations. ESC should only be turned to “Partial Off”
mode for specific reasons as noted below.
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Hill Descent Control (HDC) — Four-Wheel Drive
Models With MP3023 Two-Speed Transfer Case
Only
HDC maintains vehicle speed while descending hills
during off-road driving situations and is available in
4WD LOW range only. To enable HDC, press the HDC
switch or put the Selec-Terrain™ system in “ROCK”
mode (“ROCK” mode is only available in 4WD LOW
range).When HDC is enabled, the HDC icon will be illuminated
in the instrument cluster. HDC will automatically apply
the brakes to control downhill speed to the selected level
when necessary on grades greater than approximately
8%. It will usually not activate on level ground.
Hill Descent Switch
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Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle at or above
maximum load is dangerous. The added strain on
your tires could cause them to fail. You could have a
serious collision. Do not drive a vehicle loaded to the
maximum capacity at continuous speeds above
75 mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause a collision. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized dealer for radial tire repairs.
Spare Tire Matching Original Equipped Tire And
Wheel – If Equipped
Your vehicle may be equivalent with a spare tire and
wheel in look and function as the original equipment tire
and wheel found on the front or rear axle of your vehicle.
This spare tire may be used in the tire rotation for your
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•The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire gauge, even
if under-inflation has not reached the level to trigger
illumination of the Tire Pressure Monitoring Telltale
Light.
•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Base System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim-mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.
NOTE:It is particularly important, for you to regularly
check the tire pressure in all of your tires, and to maintain
the proper pressure. The TPMS consists of the following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A low spare tire will not cause the Tire Pressure Moni-
toring Telltale Light to illuminate, a warning message to
appear, or the chime to sound. The Tire Pressure Monitoring Telltale Light will
illuminate in the instrument cluster, a “LOW TIRE
PRESSURE” message will display in the instru-
ment cluster for 5 seconds, and an audible chime will be
activated, when one or more of the four active road tire
pressures are low. Should this occur, you should stop as
soon as possible, check the inflation pressure of each tire
on your vehicle, and inflate each tire to the vehicle’s
recommended cold placard pressure value. The system
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