2007 JEEP COMPASS wheel size

•Driver and Front Passenger Seat Belt Pretensioners
•Occupant Classification System (OCS) for the Front
Passenger Seat
Occupant Classification Module
Passenger Airbag Disable (PAD) Indicator Light
Weight Sensors
How The Airbag System Works
•
TheOccupant Restraint Controller (ORC)determines
if a frontal collision is severe enough to require the
airbags to inflate. The front airbag inflators are de-
signed 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 provided by the Occupant Classification Module.
The ORC will not detect roll over.The ORC also monitors the readiness of the electronic
parts of the system whenever the ignition switch is in
the START or RUN positions. These include all of the
items listed above except the steering wheel and
column, and knee bolsters. If the key is in the OFF
position, in the ACC position, or not in the ignition,
the airbags are not on and will not inflate.
During a moderate-to-severe rear impact the ORC may
deploy the seat belt pretensioners alone.
Also, the ORC turns on the AIRBAG warning
light and PAD indicator light in the instrument
panel for 6 to 8 seconds for a self-check when
the ignition is first turned on. After the self-
check, the AIRBAG warning light will turn off. The PAD
indicator light will function normally (Refer toPassen-
ger Airbag Disable (PAD) Indicator Lightin this section).
If the ORC detects a malfunction in any part of the
system, it turns on the AIRBAG warning light either
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authorized dealer. The Airbag Warning Light is turned on
whenever there is fault that can affect the operation of the
airbag system. If there is a fault present in the OCS, 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
may be possible based on collision severity and occu-
pant size. The steering wheel hub trim cover and theupper 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 is about 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’s front
airbag gas is vented through vent holes in the sides of
the airbag. The passenger’s front airbag gas is vented
through 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-
troller (ORC). The ORC uses the occupant category to
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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 op-
eration or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. Aftermarket 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.
23. Four-Wheel-Drive
This light indicates the vehicle is in 4WD.
24. Odometer/Trip Odometer
A vacuum fluorescent display indicates the total distance
the vehicle has been driven. Also, the cluster will display,replacing the odometer/trip odometer, vehicle warning
messages such as: door/gate ajar and loose gas cap.
Loose gas cap will be displayed from the Odometer/Trip
Odometer on all models.
NOTE:If vehicle is equipped with the optional Elec-
tronic Vehicle Information Center (EVIC) in the instru-
ment cluster, all warnings including “door”, and “gATE”
will only be displayed in the EVIC display. For additional
information, refer to “Electronic Vehicle Information Cen-
ter — If Equipped” in Section 3.
U.S. federal regulations require that upon transfer of
vehicle ownership, the seller certify to the purchaser the
correct mileage that the vehicle has been driven. There-
fore, if the odometer reading is changed during repair or
replacement, be sure to keep a record of the reading
before and after the service so that the correct mileage can
be determined.
UNDERSTANDING YOUR INSTRUMENT PANEL 173
4

When the vehicle is driven over 7 mph (11 km/h), you
may also hear a slight clicking sound as well as some
related motor noises. These noises are the system per-
forming its self check cycle to ensure that the ABS system
is working properly. This self check occurs each time the
vehicle is started and accelerated past 7 mph (11 km/h).
ABS is activated during braking under certain road or
stopping conditions. ABS-inducing conditions can in-
clude ice, snow, gravel, bumps, railroad tracks, loose
debris, or panic stops.
You also may experience the following when the brake
system goes into Anti-lock:
•The ABS motor running (it may continue to run for a
short time after the stop),
•the clicking sound of solenoid valves,
•brake pedal pulsations,
•and a slight drop or fall away of the brake pedal at the
end of the stop.
These are all normal characteristics of ABS.
WARNING!
The Anti-Lock Brake System contains sophisticated
electronic equipment that may be susceptible to
interference caused by improperly installed or high
output radio transmitting equipment. This interfer-
ence can cause possible loss of anti-lock braking
capability. Installation of such equipment should be
performed by qualified professionals.
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!
•Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspen-
sion dimensions and performance characteristics,
resulting in changes to steering, handling, and brak-
ing of your vehicle. This can cause unpredictable
handling and stress to steering and suspension com-
ponents. 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 to the left or right.
Alignment will not correct this condition. See your dealer
for proper diagnosis.
268 STARTING AND OPERATING

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.
Aftermarket 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 is not intended to replace normal tire care
and maintenance, or 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.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
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