2005 CHRYSLER VOYAGER Module

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.
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UNDEPLOYED AIRBAG
WARNING: The airbags must be stored in its origi-
nal special container until used for service. At no
time should a source of electricity be permitted
near the inflator on the back of an airbag. When
carrying or handling an undeployed airbag, the trim
side of the airbag should be pointing toward the
body to minimize the possibility of personal injury
or death if accidental deployment occurs. Do not
place undeployed airbag face down on a solid sur-
face, the airbag will propel into the air if accidental
deployment occurs.
STANDARD PROCEDURE - SERVICE AFTER AN
AIRBAG DEPLOYMENT
DRIVER AIRBAG
After a Driver Airbag has been deployed due to a
collision, the followingMUSTbe replaced:
²Driver Airbag
²Clockspring Assembly
²Steering Wheel
²Complete Steering Column Assembly w/Lower
Steering Column Coupler
All other airbag and vehicle components should be
closely inspected following any airbag deployment,
and should be replaced when visible damage is
incurred.
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.
PASSENGER AIRBAG
After a Passenger Airbag has been deployed due to
a collision. the followingMUSTbe replaced:
²Passenger Airbag
²Instrument Panel and Pad Assembly
All other airbag and vehicle components should be
closely inspected following any airbag deployment,
and should be replaced when visible damage is
incurred.
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.
KNEE BLOCKER AIRBAG
After a Knee Blocker Airbag has been deployed due
to a collision. the followingMUSTbe replaced:
²Knee Blocker Airbag
²Instrument Panel and Pad Assembly
All other airbag and vehicle components should be
closely inspected following any airbag deployment,
and should be replaced when visible damage is
incurred.
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.
CURTAIN AIRBAG
After a Curtain Airbag has been deployed due to a
collision. the followingMUSTbe replaced:
²Curtain Airbag Assembly
²Headliner
²A, B, and C-Pillar Trim on deployed side.
All other airbag and vehicle components should be
closely inspected following any airbag deployment,
and should be replaced when visible damage is
incurred.
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.
OCCUPANT CLASSIFICATION SYSTEM (OCS)
After an impact event, either front, rear, or side,
the OCS system components need to be inspected
and replaced if found to be damaged.
This includes:
²Belt Tension Sensor
²Occupant Classification Module (OCM)
²Passenger Airbag ON/Off Indicator
²Seat Weight Bladder and Sensor
RSRESTRAINTS8O-7
RESTRAINTS (Continued)

WARNING: Never replace both the Occupant Restraint
Controller (ORC) and the Occupant Classification Mod-
ule (OCM) at the same time. If both require replace-
ment, replace one, then perform the Airbag System
test (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNO-
SIS AND TESTING - AIRBAG SYSTEM) before replac-
ing 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 the same
time, an irreversible fault will be set in both modules
and the OCS may malfunction and result in personal
injury or death.
Whether replaced or not, the OCS must be re-ze-
roed to make sure that the system in within proper
parameters to sense the occupants weight correctly.
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.
WARNING: Following successful completion of the
Airbag System test procedure, the Occupant Classi-
fication System Verification Test must be done
using a scan tool and the appropriate diagnostic
information. Personal injury or death may result if
the system test is not performed.
SEAT BELTS AND TENSIONERS
After a frontal impact where an airbag has been
deployed due to a collision. the followingMUSTbe
replaced:
²Front Seat Belt Buckle (driver and passenger)
with integral Tensioners.
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.
All other seat belts should be closely inspected for
cuts, tears, fraying, or damage in any way following
any frontal impact or airbag deployment. The other
seat belts are to be replaced when visible damage is
incurred. Inspect the Lower Anchors and Tether for
CHildren (LATCH) child restraint anchors for dam-
age after an impact event and replace as needed.
CLEAN UP PROCEDURE
Roll or fold the airbag towards its mounting point
(i.e. instrument panel, steering wheel, knee blocker,curtain, or seat back). Then tape the ripped cover
over the deployed airbag if applicable.
Use a vacuum cleaner to remove any residual pow-
der from the vehicle interior. Work from the outside
in to avoid kneeling or sitting in a contaminated
area. Vacuum the heater and A/C outlets as well (Fig.
4). If the heater or air conditioner was in RECIRC
mode at time of airbag deployment, operate blower
motor on low speed and vacuum powder residue
expelled from the heater and A/C outlets. Multiple
vacuum cleaning may be necessary to decontaminate
the interior of the vehicle.
BELT TENSION SENSOR
DESCRIPTION
Vehicles equipped with the Occupant Classification
System (OCS) include a belt tension sensor (Fig. 5).
Fig. 4 VACUUM HEATER AND A/C OUTLETS - TYPICAL
Fig. 5 BELT TENSION SENSOR
1 - SEAT BELT WEBBING
2 - B-PILLAR
3 - SEAT BELT LOWER ANCHOR BOLT
4 - BELT TENSION SENSOR
8O - 8 RESTRAINTSRS
RESTRAINTS (Continued)

This sensor is integral to the passenger side front
seat belt lower anchor which is secured to the lower
B-pillar, on the passenger side (Fig. 6). The belt ten-
sion sensor consists of a molded plastic housing, a
metal seat belt anchor loop, and a short pigtail wire.
The electronic circuitry of the belt tension sensor is
concealed and protected within the molded plastic
housing.
The belt tension sensor cannot be repaired and, if
faulty or damaged, the entire passenger side front
seat belt and retractor unit must be replaced (Refer
to 8 - ELECTRICAL/RESTRAINTS/SEAT BELT
OUTBOARD FRONT - REMOVAL).
OPERATION
The belt tension sensor is designed to sense the
relative cinch load applied to the passenger side front
seat belt, which provides a logic input to the micro-
processor of the Occupant Classification Module
(OCM). When a load is applied to the seat belt, the
changes in the load are measured by the belt tension
sensor through the seat belt lower anchor. As the
load changes, the circuitry of the belt tension sensor
changes the output voltage of the sensor.
The belt tension sensor receives a nominal five
volts and a ground from the OCM. The OCM then
monitors the belt tension sensor output voltage.
WARNING: Do not connect the battery before per-
forming the OCS Verification Test using the scantool and the appropriate diagnostic information.
Personal injury or death may occur.
For further diagnosis and testing of the belt ten-
sion sensor, the OCM, and related occupant classifi-
cation system components, use a scan tool and the
appropriate diagnostic information.
CHILD RESTRAINT ANCHOR
DESCRIPTION
TheLower Anchors and Tether for CHildren,
or LATCHchild restraint anchorage system provides
for the installation of suitable child restraints in cer-
tain seating positions without using the seat belt pro-
vided for that seating position. The second seat in
these models are equipped with a fixed-position child
restraint upper tether anchor (Fig. 7) and child
restraint lower anchors (Fig. 8). The third seat is
equipped with only a fixed-position child restraint
upper tether anchor in the middle seating position.
Export vehicles are equipped with fixed-position child
restraint upper tether anchors only.
Fig. 6 BELT TENSION SENSOR LOCATION
1 - A-PILLAR
2 - SEAT BELT ANCHOR/BELT TENSION SENSOR
3 - BELT TENSION SENSOR CONNECTOR
Fig. 7 CHILD RESTRAINT UPPER TETHER/ANCHOR
- 2ND ROW
Fig. 8 CHILD RESTRAINT LOWER ANCHORS
SECOND ROW
RSRESTRAINTS8O-9
BELT TENSION SENSOR (Continued)

OCCUPANT CLASSIFICATION
MODULE
DESCRIPTION
The Occupant Classification Module (OCM) (Fig.
34) is secured with two screws to a stamped steel
mounting bracket welded onto the underside of the
passenger front seat cushion frame near the inboard
front corner (Fig. 35). Concealed within a hollow in
the center of the molded plastic OCM housing is a
microprocessor and the other electronic circuitry of
the module. The module housing is sealed to enclose
and protect the internal electronic circuitry. The
OCM software is flash programmable.
A non-calibrated OCM is the only component of the
Occupant Classification System (OCS) that is avail-
able for separate service replacement. The OCS com-
ponents of the passenger side front seat cushion
including the cushion frame, insulator pad, seat
weight bladder and pressure sensor, seat cushion
foam, wiring harness and the OCM are a factory-cal-
ibrated and assembled unit. Once this unit is con-
nected to a vehicle electrically, the calibration
settings are uploaded from the calibrated OCM and
stored in the memory of the Occupant Restraint Con-
troller (ORC). If only the OCM is subsequently
replaced, the new, non-calibrated OCM learns the
proper calibration settings from the ORC after it is
connected to the vehicle electrically.The OCM cannot be adjusted or repaired and, if
damaged or faulty, it must be replaced. The compo-
nents of the passenger front seat cushion are ser-
viced only as a factory-calibrated, assembled and
tamper-evident unit. Only the OCM and the seat
cushion trim are available for separate service
replacement. Once a service replacement package has
been installed in a vehicle, the OCM can thereafter
be serviced only by replacing the entire passenger
front seat cushion with another complete service
replacement package.
OPERATION
The microprocessor in the Occupant Classification
Module (OCM) contains the Occupant Classification
System (OCS) logic circuits. The OCM uses On-Board
Diagnostics (OBD) and can communicate with other
electronic modules in the vehicle as well as with a
scan tool using the Programmable Communications
Interface (PCI) data bus network. This method of
communication is also used for OCS diagnosis and
testing through the 16-way Data Link Connector
(DLC), located on the driver side lower edge of the
instrument panel.
The OCM provides a nominal five volts to both the
pressure sensor of the seat weight bladder beneath
the passenger front seat cushion and to the belt ten-
sion sensor on the passenger front seat belt lower
Fig. 34 OCCUPANT CLASSIFICATION MODULE
(OCM) - TYPICAL
1 - OCCUPANT CLASSIFICATION MODULE
2 - CONNECTOR LOCK TOWER
3 - CONNECTOR RECEPTACLE
4 - MOUNTING TAB (2)
Fig. 35 OCM LOCATION
1 - OCCUPANT CLASSIFICATION MODULE (OCM)
2 - LOCK TOWER
3 - LOCK PIN
4 - CONNECTOR
5 - SCREW (2)
6 - BRACKET
RSRESTRAINTS8O-25

anchor. The OCM then monitors the return voltage
from each of the sensors. The bladder pressure sen-
sor input allows the OCM to determine whether the
passenger front seat is occupied and the relative size
of the occupant by providing a weight-sensing refer-
ence to the load on the seat cushion. The belt tension
sensor provides an additional logic input to the OCM
microprocessor that allows it to distinguish between
the lower seat belt cinch loads of a belted occupant
and the higher loads associated with a belted child
seat.
Pre-programmed decision algorithms and OCS cal-
ibration allow the OCM microprocessor to determine
when the seat cushion load as signaled by the blad-
der pressure sensor and the seat belt cinch load as
signaled by the belt tension sensor indicate that pas-
senger airbag protection is appropriate. When the
programmed conditions are met, the OCM sends the
proper electronic occupant classification messages
over the PCI data bus to the Occupant Restraint
Controller (ORC), and the ORC enables or disables
the deployment circuits for the passenger front sup-
plemental restraints. The ORC also provides a con-
trol output for the Passenger Airbag Disabled (PAD)
indicator in the instrument panel center stack, based
upon the electronic occupant classification messages
it receives from the OCM.
The OCM microprocessor continuously monitors all
of the OCS electrical circuits and components to
determine the system readiness. If the OCM detects
a monitored system fault, it sets an active and stored
Diagnostic Trouble Code (DTC) and sends the appro-
priate electronic messages to the ORC over the PCI
data bus. Then the ORC sets a DTC and sends mes-
sages to control the airbag indicator operation
accordingly. An active fault only remains for the
duration of the fault, or in some cases for the dura-
tion of the current ignition switch cycle, while a
stored fault causes a DTC to be stored in memory by
the OCM and the ORC. For some DTC's, if a fault
does not recur for a number of ignition cycles, the
OCM will automatically erase the stored DTC. For
other internal faults, the stored DTC is latched for-
ever.
The OCM receives battery current from an IPM
high side driver (Run/Start). The OCM receives
ground through a ground circuit of the body wire
harness, which it shares with the ORC. These con-
nections allow the OCM to be operational whenever
the ignition switch is in the Start or ON positions.
To diagnose and test the OCS, use a scan tool and
the appropriate diagnostic information.
REMOVAL
Once any of the original factory-installed compo-
nents except the Occupant Classification Module(OCM) have been replaced with the service replace-
ment package components, the OCM can only be ser-
viced by replacing the entire passenger front seat
cushion unit with another complete service replace-
ment package (Refer to 23 - BODY/SEATS/SEAT
CUSHION - FRONT - REMOVAL).
WARNING: Never replace both the Occupant
Restraint Controller (ORC) and the Occupant Clas-
sification Module (OCM) at the same time. If both
require replacement, replace one, then perform the
Airbag System test (Refer to 8 - ELECTRICAL/RE-
STRAINTS - 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 the same time, an irreversible fault will
be set in both modules and the OCS may malfunc-
tion and result in personal injury or death.
(1) Disconnect and isolate the battery negative
cable.
(2)
WARNING: Wait two minutes for the airbag system
reserve capacitor to discharge before beginning
any airbag system or component service. Failure to
do so may result in accidental airbag deployment,
personal injury or death.
(3) Reach under the front edge of the passenger
side front seat cushion to access and remove the lock
pin from the connector lock tower on the Occupant
Classification Module (OCM) (Fig. 36).
(4) Disconnect the passenger front seat wire har-
ness connector for the OCM.
(5) Remove the two screws that secure the OCM to
the OCM bracket.
(6) Remove the OCM from under the passenger
front seat.
INSTALLATION
WARNING: To avoid personal injury or death on
vehicles equipped with the Occupant Classification
System (OCS), only the Occupant Classification
Module (OCM) and the seat cushion trim may be
serviced separately. All other components of the
passenger front seat cushion must be serviced only
as a complete factory-calibrated, assembled and
tamper-evident service replacement package.
Once any of the original factory-installed compo-
nents except the OCM have been replaced with the
service replacement package components, the OCM
can only be serviced by replacing the entire passen-
8O - 26 RESTRAINTSRS
OCCUPANT CLASSIFICATION MODULE (Continued)