2006 JEEP GRAND CHEROKEE wheel size

Driver And Front Passenger Supplemental
Restraint Systems (SRS)This vehicle has airbags for both the driver and right
front passenger as a supplement to the seat belt restraint
systems. The driver’s front airbag is mounted in the
steering wheel. The passenger side airbag is mounted in
the instrument panel, above the glove compartment. The
words SRS/AIRBAG are embossed on the airbag covers.
NOTE:The front airbags are certified to the Federal
regulations that allow less forceful deployment.
The front airbags have a multistage inflator design. This
may allow the airbag to have different rates of inflation
that are based on collision severity and occupant size.
Also, the front passenger airbag is certified to the Federal
regulations that define Occupant Classification (Refer to
Occupant Classification Systemin this section).
Front Airbag Components
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Airbag System Components
The airbag system consists of the following:
•Occupant Restraint Control Module
•Airbag Warning Light
•Driver Airbag
•Passenger Airbag
•Side Curtain Airbags above Side Windows (If
Equipped)
•Side Remote Acceleration Sensors (If Equipped)
•Steering Wheel and Column
•Instrument Panel
•Interconnecting Wiring
•Knee Impact Bolsters
•Front Acceleration Sensors
•Driver and Front Passenger Seat Belt Pretensioner
•Occupant Classification System (OCS)—Front Pas-
senger Seat Only
Occupant Classification Module
Passenger Airbag Disable (PAD) Indicator Light
Weight Sensors
How The Airbag System Works
•
TheOccupant Restraint Control (ORC) Modulede-
termines if a frontal, side, or rollover collision is severe
enough to require the front and/or side airbags to
inflate. The front airbag inflators are designed to
provide different rates of airbag inflation from direc-
tion provided by the ORC. The ORC may also modify
the rate of inflation based on the occupant size pro-
vided by the Occupant Classification Module. The
ORC will detect roll overs, not rear impacts.
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both the“PAD Indicator Light”and the“Airbag Warning
Light”are illuminated to show that the passenger airbag
is turned off until the fault is cleared. If an object is
lodged under the seat and interferes with operation of
the weight sensors, a fault will occur which turns on both
the“PAD Indicator Light”and the“Airbag Warning
Light.”Once the lodged object is removed, the fault will
be automatically cleared after a short period of time.
•TheDriver and Passenger Airbag/Inflator Unitsare
located in the center of the steering wheel and the right
side of the instrument panel. When the ORC detects a
collision requiring the airbags, it signals the inflator
units. A large quantity of nontoxic gas is generated to
inflate the front airbags. Different airbag inflation rates
are possible, based on collision severity and occupant
size. The steering wheel hub trim cover and the upper
right side of the instrument panel separate and fold
out of the way as the bags inflate to their full size. The
bags fully inflate in about 50–70 milliseconds. This isabout half of the time it takes to blink your eyes. The
bags then quickly deflate while helping to restrain the
driver and front passenger.
The driver front airbag gas is vented through the vent
holes in the sides of the airbag. The passenger front
airbag gas is vented through the vent holes in the sides
of the airbag. In this way, the airbags do not interfere
with your control of the vehicle.•TheOccupant Classification Module (OCM)is lo-
cated beneath the front passenger seat. The OCM
classifies the occupant into categories based on the
measurements made by the seat weight sensors. The
OCM communicates with the Occupant Restraint Con-
trol (ORC) Module. The ORC uses the occupant cat-
egory to determine whether the front passenger airbag
should be turned off. It also determines the rate of
airbag inflation during a collision.
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road surfaces only. Driving in the 4 LOW position on dry
hard surfaced roads may cause increased tire wear and
damage to driveline components.
When operating your vehicle in 4 LOW, the engine speed
is approximately three times that of the 4 HI position at a
given road speed. Take care not to overspeed the engine
and do not exceed 25 mph (40 km/h).
Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
Shift Positions
For additional information on the appropriate use of each
transfer case mode position, see the information below:
4HI
Four Wheel Drive High Range—All roads surfaces such
as ice, snow, gravel, sand, and dry hard pavement.
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WARNING!
•Leaving children unattended in a vehicle is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the gear selector
lever. Don’t leave the keys in the ignition. A child
could operate power windows, other controls, or
move the vehicle.
•Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up
may cause serious injury or death.
To release the parking brake, pull up slightly, press the
center button, then lower the lever completely.
Be sure the parking brake is fully disengaged before
driving. Failure to do so can lead to brake failure.NOTE:Parking brake adjustment and maintenance
should be performed by your authorized dealer.
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.
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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 Anti-Lock Brake System 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.
The Anti-Lock Brake System pump motor runs during
the self-test at 12 mph (20 km/h) and during an ABS stop.
The pump motor makes a low humming noise during
operation, which is normal.
WARNING!
Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to an accident.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
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WARNING!
•Do not use a tire, wheel size or rating other than
that specified for your vehicle. Some combina-
tions of unapproved tires and wheels may change
suspension dimensions and performance charac-
teristics, resulting in changes to steering, han-
dling, and braking of your vehicle. This can cause
unpredictable handling and stress to steering and
suspension components. You could lose control
and have an accident resulting in serious injury or
death. Use only the tire and wheel sizes with load
ratings approved for your vehicle.
•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 an accident.
•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.
Alignment and Balance
Poor suspension alignment may result in:
•Fast tire wear.
•Uneven tire wear, such as feathering and one-sided
wear.
•Vehicle pull to right or left.
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Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your autho-
rized dealer for proper diagnosis.
Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
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 check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.The“Tire Pressure Monitoring Telltale Light”will
illuminate in the instrument cluster, and an au-
dible chime will be activated when one or more
tire pressures is low. The“Tire Pressure Monitoring
Telltale Light”will flash on and off for 10 to 60 seconds
when a system fault is detected. The flash cycle will
repeat every ten minutes or until the fault condition is
removed and reset.
The Tire Pressure Monitor System (TPMS) consists of the
following components:•Receiver Module
•5 Wheel Sensors (including Full Size Spare Tire)
•Tire Pressure Monitoring Telltale Light
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