²Occupant Classification Module- Vehicles
equipped with the Occupant Classification System
(OCS) include an Occupant Classification Module
(OCM) which is secured to a stamped steel mounting
bracket on the underside of the passenger side front
seat cushion frame.
²Occupant Restraint Controller- The Occu-
pant Restraint Controller (ORC) is also sometimes
referred to as the Airbag Control Module (ACM). The
ORC is located on a mount on the floor transmission
tunnel just underneath the instrument panel center
stack (Fig. 3).
²Passenger Airbag- The passenger airbag is
located on the instrument panel, beneath the instru-
ment panel top pad and above the glove box on the
passenger side of the vehicle (Fig. 3).
²Passenger Airbag Disabled (PAD) Indicator
- Vehicles equipped with the Occupant Classification
System (OCS) include a passenger airbag disabled
(PAD) indicator which is located in the instrument
panel center stack (Fig. 3).
²Passenger Knee Blocker- The passenger knee
blocker is a structural reinforcement that is integral
to and concealed within the glove box door (Fig. 3).
²Seat Belt Tensioner- A seat belt tensioner is
integral to both front seat belt buckles. The seat belt
buckles are secured to the inner seat frame sides,
beneath a cushion trim panel.
²Seat Weight Bladder and Pressure Sensor
Assembly- Vehicles equipped with the Occupant
Classification System (OCS) include a seat weight
bladder that is sandwiched between an insulator pad
on the top of the passenger side front seat pan and
the seat cushion foam padding. A short hose connects
the bladder to a pressure sensor which is secured to
the Occupant Classification Module (OCM) mounting
bracket on the underside of the passenger side front
seat cushion frame.
²Side Impact Sensors- Six side impact sensors
are used on vehicles equipped with the curtain air-
bags, three left side and three right side. The first
row side impact sensor is located in the B-pillar, just
above the front seat belt retractor. The second row
side impact sensor is located in the sliding side door
track opening, just in front of the C-pillar. The third
row side impact sensor is located behind the quarter
trim panel, above the rear tire wheel well, between
the C and D-pillars.
The ORC, the OCM, and the cluster each contain a
microprocessor and programming that allow them to
communicate with each other using the Programma-
ble Communications Interface (PCI) data bus net-
work. This method of communication is used by the
ORC for control of the airbag indicators.OPERATION
ACTIVE RESTRAINTS
The primary passenger restraints in this or any
other vehicle are the seat belts and child restraint
anchors. Seat belts and child restraint anchors are
referred to as an active restraint because the vehicle
occupants are required to physically fasten and prop-
erly adjust these restraints in order to benefit from
them. See the owner's manual in the vehicle glove
box for more information on the features, use and
operation of all of the active restraints.
PASSIVE RESTRAINTS
The passive restraints are referred to as a supple-
mental restraint system because they were designed
and are intended to enhance the protection for the
occupants of the vehicleONLYwhen used in con-
junction with the seat belts. They are referred to as
passive restraints because the vehicle occupants are
not required to do anything to make them operate;
however, the vehicle occupants must be wearing their
seat belts in order to obtain the maximum safety
benefit from the supplemental restraint system.
The supplemental restraint system electrical cir-
cuits are continuously monitored and controlled by a
microprocessor and software contained within the
Occupant Restraint Controller (ORC). An airbag indi-
cator in the ElectroMechanical Instrument Cluster
(EMIC) illuminates for about seven seconds as a bulb
test each time the ignition switch is turned to the
ON or START positions. Following the bulb test, the
airbag indicator is turned ON or OFF by the ORC to
indicate the status of the supplemental restraint sys-
tem. If the airbag indicator comes ON at any time
other than during the bulb test, it indicates that
there is a problem in the supplemental restraint sys-
tem electrical circuits. Such a problem may cause air-
bags not to deploy when required, or to deploy when
not required.
Deployment of the supplemental restraints
depends upon the angle and severity of an impact.
Deployment is not based upon vehicle speed; rather,
deployment is based upon the rate of deceleration as
measured by the forces of gravity (G force) upon the
impact sensors. When an impact is severe enough,
the microprocessor in the ORC signals the inflator of
the appropriate airbag units to deploy their airbag
cushions. The front seat belt tensioners are provided
with a deployment signal by the ORC in conjunction
with the front airbags. During a frontal vehicle
impact, the knee blockers work in concert with prop-
erly fastened and adjusted seat belts to restrain both
the driver and the front seat passenger in the proper
position for an airbag deployment. The knee blockers
also absorb and distribute the crash energy from the
8O - 4 RESTRAINTSRS
RESTRAINTS (Continued)
driver and the front seat passenger to the structure
of the instrument panel (Refer to 8 - ELECTRICAL/
RESTRAINTS/KNEE BLOCKER AIRBAG -
DESCRIPTION). The seat belt tensioners remove the
slack from the front seat belts to provide further
assurance that the driver and front seat passenger
are properly positioned and restrained for an airbag
deployment.
When the ORC monitors a problem in any of the
dual front airbag system circuits or components,
including the seat belt tensioners, it stores a Diag-
nostic Trouble Code (DTC) in its memory and sends
an electronic message to the EMIC to turn on the
airbag indicator. Proper testing of the supplemental
restraint system components, the Programmable
Communications Interface (PCI) data bus, the elec-
tronic message inputs to and outputs from the EMIC
or the ORC, as well as the retrieval or erasure of a
DTC from the ORC or the EMIC requires the use of
a scan tool. Refer to the appropriate diagnostic infor-
mation.
OCCUPANT CLASSIFICATION SYSTEM
The Occupant Classification System (OCS) auto-
matically suppresses or enables passenger airbag and
seat belt tensioner operation based upon whether or
not the passenger side front seat is occupied and, if
the seat is occupied, classifies the size of the occu-
pant and whether the seat is occupied by a child
seat.
The OCS has an Occupant Classification Module
(OCM) that monitors inputs from the seat weight
bladder pressure sensor under the passenger side
front seat cushion and from the belt tension sensor
on the passenger side front seat belt lower anchor.
Based upon those inputs the microprocessor within
the OCM classifies the occupant of the passenger
side front seat. The OCM then sends electronic occu-
pant classification messages to the ORC. The micro-
processor and programming of the ORC uses these
occupant classification messages to determine
whether to enable or disable the deployment circuits
for the passenger airbag and seat belt tensioner.
The OCS electrical circuits and components are
continuously monitored by the OCM, and the OCM is
continuously monitored by the ORC. A passenger air-
bag ON/OFF indicator is located in the instrument
panel center stack area. This indicator receives bat-
tery current whenever the ignition switch is in the
ON or START positions, and illuminates only when
the ORC pulls the indicator control circuit to ground.
The indicator illuminates for about seven seconds as
a bulb test each time the ignition switch is turned to
the ON or START positions. Following the bulb test,
the indicator is turned ON or OFF by the ORC based
upon the electronic occupant classification messagesreceived from the OCM. This indicator is illuminated
whenever the passenger airbag and seat belt ten-
sioner operation has been suppressed, and is turned
OFF whenever they are enabled or when the passen-
ger seat is classified as empty.
When the OCM monitors a problem in any of the
OCS circuits or components, it stores a fault code or
DTC in its memory circuit and sends an electronic
message to the ORC. The ORC then sends an elec-
tronic message to the EMIC to turn ON the airbag
indicator. If for any reason the OCM is unable to
classify the occupant it sends an electronic message
to the ORC, and the ORC suppresses passenger air-
bag and seat belt tensioner operation. Proper testing
of the OCS components, the Programmable Commu-
nications Interface (PCI) data bus, the electronic
message inputs to and outputs from the OCM, the
EMIC or the ORC, as well as the retrieval or erasure
of a DTC's, requires the use of a scan tool. Refer to
the appropriate diagnostic information.
WARNING
WARNINGS
Disconnect and isolate the battery negative
cable before beginning any airbag system com-
ponent diagnosis, testing, removal, or installa-
tion procedures. Allow system capacitor to
discharge for two minutes before beginning any
component testing or service. This will disable
the airbag system. Failure to disconnect the
battery negative cable may result in accidental
airbag deployment, personal injury, or death.
Do not place an intact undeployed airbag
face down on a solid surface. The airbag will
propel into the air if accidentally deployed and
may result in personal injury or death.
When carrying or handling an undeployed
airbag, the trim side (face) of the airbag should
be pointing towards the body to minimize pos-
sibility of injury if accidental deployment
occurs. Failure to do this may result in per-
sonal injury or death.
Replace airbag system components with
Mopartreplacement parts. Substitute parts
may appear interchangeable, but internal dif-
ferences may result in inferior occupant protec-
tion. Failure to do so may result in occupant
personal injury or death.
Wear safety glasses, rubber gloves, and long
sleeved clothing when cleaning powder residue
from vehicle after airbag deployment. Sodium
hydroxide powder residue emitted from a
deployed airbag can cause skin irritation.
Flush affected area with cool water if irritation
is experienced. If nasal or throat irritation is
RSRESTRAINTS8O-5
RESTRAINTS (Continued)
experienced, exit the vehicle for fresh air until
the irritation ceases. If irritation continues, see
a physician.
Do not use a replacement airbag that is not in
the original packaging. This may result in
improper deployment, personal injury, or
death.
The factory installed fasteners, screws and
bolts used to fasten airbag components have a
special coating and are specifically designed
for the airbag system. Do not use substitute fas-
teners. Use only original equipment fasteners
listed in the parts catalog when fastener
replacement is required.
During, and following, any child restraint
anchor service, due to impact event or vehicle
repair, carefully inspect all mounting hard-
ware, tether straps, and anchors for proper
installation, operation, or damage. If a child
restraint anchor is found damaged in any way,
the anchor must be replaced. Failure to do this
may result in personal injury or death.
Deployed and nondeployed airbags may or
may not have live pyrotechnic material within
the airbag inflator. Do not dispose of driver/
passenger/seat/curtain/knee blocker airbags or
seat belt tensioners unless you are sure of com-
plete deployment. Refer to the Hazardous Sub-
stance Control System for proper disposal.
Dispose of deployed airbags and tensioners
consistent with state, provincial, local, and fed-
eral regulations.
After any airbag component testing or ser-
vice, do not connect the battery negative cable
(Refer to 8 - ELECTRICAL/RESTRAINTS -
DIAGNOSIS AND TESTING - AIRBAG SYSTEM).
Personal injury or death may result if the sys-
tem test is not performed first.
If the vehicle is equipped with the Occupant
Classification System (OCS), do not connect the
battery negative cable before performing the
OCS Verification Test using the scan tool and
the appropriate diagnostic information. Per-
sonal injury or death may result if the system
test is not performed properly.
Never replace both the Occupant Restraint
Controller (ORC) and the Occupant Classifica-
tion Module (OCM) at the same time. If both
require replacement, replace one, then perform
the Airbag System test (Refer to 8 - ELECTRI-
CAL/RESTRAINTS - DIAGNOSIS AND TESTING
- AIRBAG SYSTEM) before replacing the other.
Both the ORC and the OCM store Occupant
Classification System (OCS) calibration data,
which they transfer to one another when one of
them is replaced. If both are replaced at thesame time, an irreversible fault will be set in
both modules and the OCS may malfunction
and cause personal injury or death.
DIAGNOSIS AND TESTING - AIRBAG SYSTEM
(1) With the battery negative remote cable discon-
nected, connect the scan tool to the Data Link Con-
nector (DLC).
(2) Turn the ignition key to the ON position, then
exit vehicle with the scan tool.
(3) After checking that no one is inside the vehicle,
connect the battery negative remote terminal.
(4) Read and record theACTIVEDiagnostic Trou-
ble Code (DTC) data.
(5) Read and record anySTOREDDTC's.
(6) Refer to the proper diagnostic information if
any DTC's are found in Step 4 and Step 5.
(7) If the airbag warning lamp either fails to light,
or goes ON and stays ON, there is a system malfunc-
tion. To test the airbag warning lamp (bulb) opera-
tion in the cluster (Refer to 8 - ELECTRICAL/
INSTRUMENT CLUSTER - DIAGNOSIS AND
TESTING). Refer to the proper diagnostic informa-
tion for any other system problems.
STANDARD PROCEDURE
STANDARD PROCEDURE - HANDLING
AIRBAGS
DEPLOYED AIRBAG
WARNING: The vehicle interior may contain a very
small amount of powder, a by-product of airbag
deployment. This powder can irritate the skin, eyes,
nose and throat. Wear safety glasses, rubber
gloves, and long sleeved clothing when cleaning
any of the powder residue from the vehicle. If you
find that the cleanup is irritating your skin, run cool
water over the affected area. Also, if you experience
nasal or throat irritation, exit the vehicle for fresh
air until the irritation ceases. If irritation continues,
see a physician.
8O - 6 RESTRAINTSRS
RESTRAINTS (Continued)
(28) Install two right side nuts at instrument
panel center stack support to floor.
(29) Install two left side nuts at instrument panel
center stack support to floor.
(30) Connect the two wiring connectors to lower
instrument panel cubby bin at bottom of center stack
and install six screws.
(31) Align left side upper A-pillar trim over retain-
ing slots and firmly snap into place.
(32) Install four nuts at brake pedal support
bracket to instrument panel.
(33) Align left A-pillar lower extension trim over
retaining slots and firmly snap into place.
(34) Install knee blocker and retaining screws.
(35) Install Data Link Connector (DLC) into bot-
tom of knee blocker.
(36) Align parking brake lever and snap into place
on knee blocker reinforcement.
(37) Install lower steering column cover and four
retaining screws
(38) Align left cowl panel over retaining slots and
firmly snap into place.
(39) Align left front door sill plate over retaining
slots and firmly snap into place.
(40) Install center console bin between front seats.
WARNING: Do not connect the battery negative
cable (Refer to 8 - ELECTRICAL/RESTRAINTS -
DIAGNOSIS AND TESTING - AIRBAG SYSTEM). Per-
sonal injury or death may result if the system test
is not performed first.
(41) Close hood.
(42) Verify system and vehicle operation.
PASSENGER AIRBAG
DISABLED INDICATOR
DESCRIPTION
Vehicles equipped with the Occupant Classification
System (OCS) include a Passenger Airbag Disabled
(PAD) indicator (Fig. 40) which is located in the
instrument panel center stack, above the radio. The
PAD indicator is present only in vehicles equipped
with the OCS.The PAD indicator consists of a molded plastic
housing with an integral connector at the back. An
amber Light Emitting Diode (LED) behind the lens
causes the ªPASS AIR BAG OFFº text and icon to
appear silhouetted against an amber field through
the translucent lens when the indicator is illumi-
nated from behind by the LED. The PAD indicator is
available for separate service replacement.
OPERATION
In vehicles equipped with the Occupant Classifica-
tion System (OCS), the Passenger Airbag Disabled
(PAD) indicator gives an indication when the passen-
ger airbag and seat belt tensioner deployment cir-
cuits are disabled by the Occupant Restraint
Controller (ORC). The PAD indicator is controlled by
a transistor within the ORC through a hard wired
output based upon ORC programming and electronic
occupant classification messages received by the ORC
over the Programmable Communications Interface
(PCI) data bus from the Occupant Classification
Module (OCM). The PAD indicator Light Emitting
Diode (LED) is completely controlled by the ORC.
The LED receives a battery current input on the
fused ignition switch output (RUN/START) circuit.
Therefore, the LED will always be OFF when the
ignition switch is in any position except ON or
START. The LED only illuminates when it is pro-
vided a path to ground by the ORC transistor. The
ORC will turn on the PAD indicator for the following
reasons:
²Bulb Test- Each time the ignition switch is
turned to the ON position the PAD indicator is illu-
minated for about six seconds.
²Child Seat Detected Occupant Classifica-
tion Message- Each time the ORC receives a mes-
sage from the OCM indicating a child seat has been
detected in the passenger front seat, the passenger
airbag and seat belt tensioner deployment circuits
are deactivated and the PAD indicator will be illumi-
nated. The indicator remains illuminated until the
ORC receives an occupant classification message
indicating that:
²The passenger front seat is empty.
²The seat is occupied by a load equal to or
greater than a fifth percentile female.
²OR,Until the ignition switch is turned to the
OFF position, whichever of these three occurs first.
²Load Less Than Fifth Percentile Female
Occupant Classification Message- Each time the
ORC receives a message from the OCM indicating
that a load less than a fifth percentile female has
been detected in the passenger front seat, the pas-
senger airbag and seat belt tensioner deployment cir-
cuits are deactivated and the PAD indicator will be
illuminated. The indicator remains illuminated until:
Fig. 40 PASSENGER AIRBAG DISABLED (PAD)
INDICATOR
RSRESTRAINTS8O-33
PASSENGER AIRBAG (Continued)
VTSS/SKIS INDICATOR LAMP
DESCRIPTION
The Sentry Key Remote Entry System (SKREES)
uses an indicator light to convey information on the
status of the system to the customer. This light is
shared with the Vehicle Theft Security System
(VTSS). The light is located in the Mechanical
Instrument Cluster (MIC). The VTSS status is con-
trolled by the Body Control Module (BCM), via Pro-
grammable Communication Interface (PCI) data bus
communication with the MIC, based upon messages
it receives from the Sentry Key Remote Entry Mod-
ule (SKREEM) on the PCI data bus.
OPERATION
The Mechanical Instrument Cluster (MIC) per-
forms a four second bulb check via PCI communica-
tion with the Sentry Key Remote Entry Module
(SKREEM). After the bulb check, the lamp is con-
trolled according to SKREEM messages. Then, the
SKREEM sends messages to the BCM to operate thelight based upon the results of the Sentry Key
Remote Entry System (SKREES) self tests. The light
may be actuated in two possible ways, flashing or on
solid. If the light comes on and stays on solid after a
power-up test, this indicates that the SKREEM has
detected a system malfunction. If the SKREEM
detects an invalid key when the ignition switch is
moved to the ON position, it sends a message on the
PCI bus to the MIC, to flash the light. The SKREEM
can also send a message to flash the light and gen-
erate a single audible chime at the same time. These
two events occurring simultaneously indicate that
the SKIS has been placed into the9Customer Learn9
mode (Refer to 8 - ELECTRICAL/VEHICLE THEFT
SECURITY/TRANSPONDER KEY - STANDARD
PROCEDURE). If the light comes on and stays on
after the power-up test, diagnosis of the SKREES
should be performed using a DRBIIItscan tool and
the appropriate Body Diagnostic Procedures informa-
tion. The light is a Light Emitting Diode (LED) and
is not a serviceable component.
8Q - 8 VEHICLE THEFT SECURITYRS