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 (If Equipped)
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.
52 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

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.
WARNING!
Significant over or under inflation of tires can lead
to loss of braking effectiveness.
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WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolong operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and should be avoided when
possible. Damage to the power steering pump may
occur.
TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P (Passenger)-Metric tire sizing is based on U.S. design
standards. P-Metric tires have the letter “P” molded
into the sidewall preceding the size designation. Ex-
ample: P215/65R15 95H.
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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.
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.
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The system consists of tire pressure monitoring sensors
attached to each wheel through the valve stem mounting
hole, a central receiver module, Wheel Sensor Trigger
Modules mounted in three of the four wheel wells,
various Tire Pressure Monitoring System Display Mes-
sages in the EVIC, and a “Tire Pressure Monitoring
Telltale Light.”
NOTE:For vehicles with optional wheel/tire sizes and
significantly different tire placard pressures, the placard
pressure value and the low-pressure threshold value is
re-programmable at your authorized dealer to accommo-
date the customer selected wheel/tire combinations rec-
ommended by DaimlerChrysler Corporation.
The followingwarningswill cause a text message to be
displayed, an audible chime to sound, and the “Tire
Pressure Monitoring Telltale Light” to illuminate. The
audible chime will occur once every ignition cycle for
eachwarningdetected. The “Tire Pressure MonitoringTelltale Light” will illuminate continuously (solid) and
shall remain illuminated until the warning condition is
removed/reset.
When the appropriate conditions exist, the Electronic
Vehicle Information Center (EVIC) displays the following
messages.
LEFT FRONT, LEFT REAR, RIGHT FRONT,
RIGHT REAR LOW PRESSURE
One or more of these messages will be displayed in the
EVIC if a low tire pressure condition exists in one or more
tires.
Inspect all tires for proper inflation pressure, once the
proper tire pressure has been set, the TPMS will reset
automatically when the vehicle has been driven for at
least 2 minutes at or above 15 mph (24 km/h).
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CHECK TPM SYSTEM
See your authorized dealer when this message appears in
the EVIC. This message indicates that a system fault
condition has been detected.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the wheel rim sensor.
NOTE:
•The TPMS can inform the driver of a low tire pressure
condition.
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
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