Airbag System Components
The airbag system consists of the following:
•Occupant Restraint Control Module
•Airbag Warning Light
•Driver Airbag
•Passenger Airbag
•Front Seat Mounted Side Airbags (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, or side 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 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.
52 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
The OCS classifies an occupant using weight sensors
mounted in the base of the front passenger seat. Any
weight on the seat will be sensed by the system. Objects
hanging on the seat or other passengers pushing down
on the seat will also be sensed. The weight of an adult
will cause the system to turn the airbag on. In this case,
the OCS has classified the occupant of the seat as an
adult. An adult occupant needs to sit in a normal position
(with their feet on or near the floor) in order to be
properly classified. Reclining the seat back too far may
change how an occupant is classified by the OCS.
Drivers and adult passengers should verify that the
“PAD Indicator Light” is not illuminated when an adult
is riding in the front passenger seat. If an adult occu-
pant’s weight is transferred to another part of the vehicle
(like the door or instrument panel), the weight sensors in
the seat may not properly classify the occupant. Objects
lodged under the seat or between the seat and the center
console can prevent the occupant’s weight from beingmeasured properly and may result in the occupant being
improperly classified. Ensure that the front passenger
seat back does not touch anything placed on the back seat
because this can also affect occupant classification. Also,
if you fold down the rear seat check to be sure it doesn’t
touch the front passenger seat.
If the front passenger seat is damaged in any way, it
should only be serviced by an authorized dealer. If the
seat is removed (or even if the seat attachment bolts are
loosened or tightened in any way), take the vehicle to an
authorized dealer.
If there is a fault present in the OCS, the “Airbag Warning
Light” (a red light located in the center of the instrument
cluster directly in front of the driver) will be turned on.
This indicates that you should take the vehicle to an
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,
56 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
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.
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 57
2
•Your vehicle has fourWeight Sensorslocated between
the seat and the floor pan. The weight sensors measure
applied weight and transfers that information to the
OCM.
•TheSide Impact (SRS) Seat Mounted Side Airbags
(If Equipped)are designed to activate only in certain
side collisions.
The ORC module determines if a side collision is
severe enough to require the side airbags to inflate.
The ORC Module monitors the readiness of the electronic
parts of the system whenever the ignition switch is in the
START or ON positions. These include all of the items
previously mentioned.
In moderate to severe side collisions, the side airbag
inflator on the crash side of the vehicle is triggered,
releasing a quantity of nontoxic gas. The inflating sideairbag exits through the seat seam into the space between
the occupant and the door. The side airbag moves at a
very high speed and with such a high force, that it could
injure you if you are not seated properly, or if items are
positioned in the area where the side airbag inflates. This
especially applies to children.
•TheKnee Impact Bolstershelp protect the knees of
the driver and the front passenger, and position every-
one for the best interaction with the front airbag.
The front passenger seat assembly contains critical com-
ponents that affect the front passenger airbag deploy-
ment. Correctly functioning front passenger seat compo-
nents are critical for the Occupant Classification System
(OCS) to properly classify the front passenger and calcu-
late the proper airbag deployment. Do not make any
modifications to the front passenger seat components,
assembly, or to the seat cover.
58 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
NOTE:Perchlorate Material – special handling may apply,
See www.dtsc.ca.gov/hazardouswaste/perchlorate
Airbag Warning Light
You will want to have the airbag system ready to inflate
for your protection in an impact. The airbag system is
designed to be maintenance free. If any of the following
occurs, have an authorized dealer service the system
promptly:
•Does not come on during the 6 to 8 seconds after the
ignition switch is first turned on.
•Remains on after the 6 to 8 second interval.
•Comes on for any period of time while driving.
Event Data Recorder (EDR)
In the event of an accident, your vehicle is designed to
record up to 5-seconds of specific vehicle data parameters
(see the following list) in an event data recorder prior to
the moment of airbag deployment, or near deployment,and up to a quarter second of high-speed deceleration
data during and/or after air bag deployment or near-
deployment. EDR data are ONLY recorded if an airbag
deploys, or nearly deploys, and are otherwise unavail-
able.
NOTE:
•A near-deployment event occurs when the airbag
sensor detects severe vehicle deceleration usually in-
dicative of a crash, but not severe enough to warrant
airbag deployment.
•Under certain circumstances, EDR data may not be
recorded (e.g., loss of battery power).
In conjunction with other data gathered during a com-
plete accident investigation, the electronic data may be
used by DaimlerChrysler Corporation and others to learn
more about the possible causes of crashes and associated
injuries in order to assess and improve vehicle perfor-
mance. In addition to crash investigations initiated by
62 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
NOTE:Anytime the ESP system is in the “Full Off”
mode, ERM is disabled. Refer to ESP (Electronic Stability
Program) for a complete explanation of the available ESP
modes.
WARNING!
Many factors, such as vehicle loading, road condi-
tions and driving conditions, influence the chance
that wheel lift or rollover may occur. ERM cannot
prevent all wheel lift or rollovers, especially those
that involve leaving the roadway or striking objects
or other vehicles. Only a safe, attentive, and skillful
driver can prevent accidents. The capabilities of an
ERM-equipped vehicle must never be exploited in a
reckless or dangerous manner which could jeopar-
dize the user’s safety or the safety of others.
ESP (Electronic Stability Program)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESP cor-
rects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in counter-
acting the over/under steer condition. Engine power
may also be reduced to help the vehicle maintain the
desired path.
ESP uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESP applies the brake of the appropri-
ate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
110 UNDERSTANDING THE FEATURES OF YOUR VEHICLE
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.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver ’s responsibility to
maintain correct tire pressure, even if under-inflation has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.
The “Tire Pressure Monitoring Telltale Light” will illumi-
nate in the instrument cluster, and an audible chime will
be activated when one or more tire pressures is low. The
“Tire Pressure Monitoring Telltale Light” will flash on
and off for 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.CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warnings 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. 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.
UNDERSTANDING YOUR INSTRUMENT PANEL 207
4
(241 kPa). If the ambient temperature is 65°F (18°C) and
the measured tire pressure is 30 psi (207 kPa), a tempera-
ture drop to 20°F (-7°C) will decrease the tire pressure to
approximately 26 psi (179 kPa). This tire pressure is
sufficiently low enough to turn ON the “Tire Pressure
Monitoring Telltale Light.” Driving the vehicle may cause
the tire pressure to rise to approximately 30 psi (207 kPa),
but the “Tire Pressure Monitoring Telltale Light” will still
be ON. In this situation, the “Tire Pressure Monitoring
Telltale Light” will turn OFF only after the tires have been
inflated to the vehicle’s recommended cold placard pres-
sure value.
Base System — If Equipped
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 Monitor System (TPMS) consists of the
following components:
•Receiver Module
•4 Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly. The matching full size
spare tire can be used in place of any of the four road
tires.
318 STARTING AND OPERATING