2008 JEEP LIBERTY wheel size

Airbag System Components
The airbag system consists of the following:
²Occupant Restraint Controller (ORC)
²Airbag Warning Light
²Driver Airbag
²Front Passenger Airbag
²Side Curtain Airbags above Side Windows
²Side Remote Acceleration Sensors
²Steering Wheel and Column
²Instrument Panel
²Interconnecting Wiring
²Front Acceleration Sensors
²Driver and Front Passenger Seat Belt Pretensioner and
Retractor
²Front Passenger Seat Track Position Sensors
²Occupant Classification System (OCS) Ð Front Pas-
senger Seat Only
þOccupant Classification Module (OCM)
þPassenger Airbag Disable (PAD) Indicator Light
þWeight Sensors
How The Airbag System Works
²
TheOccupant Restraint Controller (ORC)determines
if a frontal, side, or rollover collision is severe enough
to require the airbags to inflate. The front airbag
inflators are designed to provide different rates of
airbag inflation from direction provided by the ORC.
The ORC may also modify the rate of inflation based
on the occupant size. The ORC receives this data from
the Occupant Classification Module (OCM). The ORC
will detect roll over, but not rear impacts.
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The ORC also monitors the readiness of the electronic
parts of the system whenever the ignition switch is in
the START or ON position. These include all of the
items listed above except the Passenger Airbag Disable
(PAD) Indicator Light, the instrument panel, and the
steering wheel and column. If the key is in the LOCK
position, in the ACC position, or not in the ignition,
the airbags are not on and they will not inflate.
The ORC also turns on the ªAirbag Warning
Lightº and ªPAD Indicator Lightº for 6 to 8
seconds as a self-check when the ignition is
first turned ON. After the self-check, the
ªAirbag Warning Lightº will turn off. The ªPAD
Indicator Lightº will function normally (refer to infor-
mation on Passenger Airbag Disable (PAD) Indicator
Light in this section). If the ORC detects a malfunction
in any part of the system, it turns on the ªAirbagWarning Lightº either momentarily or continuously. A
single chime will sound if the light comes on again
after initial start up.
WARNING!
Ignoring the ªAirbag Warning Lightº in your instru-
ment panel could mean you won't have the airbags to
protect you in a collision. If the light does not come
on, stays on after you start the vehicle, or if it comes
on as you drive, have the airbag system checked right
away.
²TheOccupant Classification System (OCS)is part of
a Federally regulated safety system required for this
vehicle. It is designed to turn off the front passenger
airbag for an empty seat and for occupants classified
in a category other than that of an adult. This could be
a child, teenager, or even a small size adult.
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lodged under the seat and interferes with operation of
the weight sensors, a fault will occur which turns on both
the ªPAD Indicator Lightº and the ªAirbag Warning
Light.º Once the lodged object is removed, the fault will
be automatically cleared after a short period of time.
²TheDriver and Passenger Airbag/Inflator Unitsare
located in the center of the steering wheel and the
passenger 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 passenger 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 is about half of the time that it takes
to blink your eyes. The bags then quickly deflate while
helping to restrain the driver and front passenger. Thedriver's front airbag gas is vented through the vent
holes in the sides of the airbag. The passenger's 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.²TheOccupant 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-
troller (ORC). The ORC uses the occupant category to
determine whether the front passenger airbag should
be turned off. It also determines the rate of airbag
inflation during a collision.
²Your vehicle has fourWeight Sensorslocated between
the seat and the floor pan. The weight sensors measure
applied weight and transfers that information to the
OCM.
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CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Do not use aftermarket tire sealants
or balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result. (Refer to
ªTire Inflation Pressuresº under ªTires Ð General
Informationº and to ªTire Pressure Monitor System
(TPMS)º in Section 5 of this manual for more
information).5. Electronic Throttle Control (ETC) Warning Light Ð
If Equipped
This light informs you of a problem with the
Electronic Throttle Control system. If a problem
is detected, the light will turn on while the
engine is running. If the light remains lit with
the engine running your vehicle will usually be drivable
and not need towing, however see your authorized
dealer for service as soon as possible.
If the light is flashing when the engine is running, you
may experience power loss, an elevated/rough idle, and
increased brake pedal effort, and your vehicle may
require towing. Immediate service is required.
The light will turn on when the ignition switch is first
turned ON, and remain on briefly as a bulb check. This is
normal. If the light does not turn on during starting, have
the system checked by an authorized dealer.
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CAUTION!
²Do not attempt to make a shift while only the front wheels
or rear wheels are spinning. The MP1522 Command-Tract
transfer case is not equipped with a synchronizer and
therefore the speed of the front driveshaft and rear drive-
shaft must be equal for the shift to take place. Shifting
while only the front wheels or rear wheels are spinning can
cause damage to the transfer case.
²The 4WD Lock position and 4WD Low position are in-
tended for loose or slippery road surfaces only. Driving in
these positions on dry hard surfaced roads may cause
increased tire wear and damage to the driveline compo-
nents.
²When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD posi-
tion or 4WD LOCK position at a given road speed. Take
care not to over-speed the engine and do not exceed 25 mph
(40 km/h).
²Proper operation of 4-wheel drive vehicles depends on tires
of equal size, type, and circumference on each wheel. Any
difference in tire size can cause damage to the transfer case.
WARNING!
²You or others could be injured if you leave the
vehicle unattended with the transfer case in the
Neutral (N) position without first fully engaging
the parking brake. The transfer case Neutral (N)
position disengages both the front driveshaft and
rear driveshaft from the powertrain and it will
allow the vehicle to move despite the transmission
position. The parking brake should always be
applied when the driver is not in the vehicle.
²Always engage the parking brake when powering
down the vehicle if the ªSERV 4WDº light is
illuminated. Not engaging the parking brake may
allow the vehicle to roll, which may cause personal
injury.
²Since 4-wheel drive provides improved traction,
there is a tendency to exceed safe turning and
stopping speeds. Do not go faster than road condi-
tions permit. You or others could be injured.
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CAUTION!
²The 4WD Low position is intended for loose or
slippery road surfaces only. Driving in this posi-
tion on dry hard surfaced roads may cause in-
creased tire wear and damage to the driveline
components.
²When operating your vehicle in 4WD LOW, the
engine speed is approximately three times that of
the 2WD position or 4WD AUTO position at a
given road speed. Take care not to over-speed the
engine and do not exceed 25 mph (40 km/h).
²Proper operation of 4-wheel drive vehicles de-
pends on tires of equal size, type, and circumfer-
ence on each wheel. Any difference in tire size can
cause damage to the transfer case.
WARNING!
²You or others could be injured if you leave the
vehicle unattended with the transfer case in the
Neutral (N) position without first fully engaging
the parking brake. The transfer case Neutral (N)
position disengages both the front driveshaft and
rear driveshaft from the powertrain and it will
allow the vehicle to move despite the transmission
position. The parking brake should always be
applied when the driver is not in the vehicle.
²Always engage the parking brake when powering
down the vehicle if the ªSERV 4WDº light is
illuminated. Not engaging the parking brake may
allow the vehicle to roll, which may cause personal
injury.
²Since 4-wheel drive provides improved traction,
there is a tendency to exceed safe turning and
stopping speeds. Do not go faster than road con-
ditions permit. You or others could be injured.
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WARNING!
²Always apply the parking brake fully when leav-
ing your vehicle or it may roll and cause damage or
injury. Also, be certain to leave an automatic
transmission in ªPº (Park) or a manual transmis-
sion in ªRº (Reverse) or 1st gear. Failure to do so
may allow the vehicle to roll and cause damage or
injury.
²Leaving children in a vehicle unattended is dan-
gerous for a number of reasons. A child or others
could be injured. Don't leave the keys in the
ignition. A child could operate power windows,
other controls, or move the vehicle.
²Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
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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