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Chrysler 300/300 Touring/300C, Dodge Magnum. Manual - part 755

INSTALLATION

FRONT SEAT BELT BUCKLE

1. Position the front seat belt buckle onto the stud

near the rear of the inboard seat cushion frame.

2. Install the retaining nut onto seat cushion frame.

Tighten the nut to 43 N·m (32 ft. lbs.)

3. Connect the seat belt buckle electrical connector.

4. Install the seat cushion side shield.

5. Install floor console (Refer to 23 - BODY/INTERI-

OR/FLOOR CONSOLE - INSTALLATION).

WARNING: 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 system
test is not performed first.

WARNING: Following successful completion of the
Airbag System test procedure, the Occupant Classification System Verification Test must be done using a
scan tool and the appropriate diagnostic information.

REAR SEAT BELT BUCKLE

1. Position the rear seat belt buckle onto mounting

studs (3).

2. Install retaining nut. Torque nut to 34 N·m (25 ft.

lbs.).

3. Install rear seat cushion (Refer to 23 - BODY/

SEATS/SEAT

CUSHION

COVER

INSTALLATION).

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RESTRAINTS - SERVICE INFORMATION

SEAT BELT TENSIONER

DESCRIPTION

Seat Belt Tensioners supplement the dual front air-
bags. The seat belt tensioners are integral to the front
seat belt retractors (2), which are secured to the inner
B-pillar (1) on the right and left sides of the vehicle.
The retractor is concealed beneath the lower B-pillar
trim. The seat belt tensioner consists primarily of a
sprocket/pinion, a steel tube, a cast metal housing,
numerous steel balls, a stamped metal ball trap, a tor-
sion bar, a small pyrotechnically activated gas gener-
ator, and a short pigtail wire. All of these components
are located on one side of the retractor spool on the
outside of the retractor housing except for the torsion
bar, which serves as the spindle upon which the
retractor spool rides. The seat belt tensioners are con-
trolled by the Occupant Restraint Controller (ORC)
and are connected to the vehicle electrical system
through the body wire harness (3).

The seat belt tensioners cannot be repaired and, if
faulty or damaged, the entire front seat belt and
retractor unit must be replaced. If the front airbags have been deployed, the seat belt tensioners have also been
deployed. The seat belt tensioners are not intended for reuse and must be replaced following any front airbag
deployment. A growling or grinding sound while attempting to operate the seat belt retractor is a sure indication that
the seat belt tensioner has been deployed and requires replacement. Refer to the proper Body Diagnostic Proce-
dures manual for diagnosis and testing.

OPERATION

The seat belt tensioners are deployed in conjunction with the front airbags by a signal generated by the Occupant
Restraint Controller (ORC) through the driver or passenger seat belt tensioner line 1 and line 2 (or squib) circuits.
When the ORC sends the proper electrical signal to the tensioners, the electrical energy generates enough heat to
initiate a small pyrotechnic gas generator. The gas generator is installed in one end of a steel tube that contains
numerous steel balls. As the gas expands, it pushes the steel balls through the tube into a cast metal housing,
where a ball guide directs the balls into engagement with the teeth of a sprocket that is geared to one end of the
retractor spool. As the balls drive past the sprocket, the sprocket turns and drives the seat belt retractor spool caus-
ing the slack to be removed from the front seat belts. The ball trap captures the balls as they leave the sprocket and
are expelled from the housing.

Removing excess slack from the front seat belts not only keeps the occupants properly positioned for an airbag
deployment following a frontal impact of the vehicle, but also helps to reduce injuries that the occupant might expe-
rience in these situations as a result of harmful contact with the steering wheel, steering column, instrument panel
and/or windshield. Also, the seat belt tensioner torsion bar that the retractor spool rides upon is designed to deform
in order to control the loading being applied to the occupants by the seat belts during a frontal impact, further reduc-
ing the potential for occupant injuries.

The ORC monitors the condition of the seat belt tensioners through circuit resistance, and will illuminate the airbag
indicator in the instrument cluster and store a Diagnostic Trouble Code (DTC) for any fault that is detected. For
proper diagnosis of the seat belt tensioners, a scan tool is required and the appropriate body diagnostic information.

RESTRAINTS - SERVICE INFORMATION

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SEAT TRACK POSITION SENSOR

DESCRIPTION

The seat track position sensor (1) is a Hall Effect-type
sensor. This sensor consists of a Hall Effect Integrated
Circuit (IC) chip encased in potting material within a
cavity of the molded plastic sensor housing. The sen-
sor housing has two integral snap features (3) and
snaps into a stamped metal bracket located on the
lower outboard seat adjuster track. A molded connec-
tor (2) integral to the sensor housing is connected to
the vehicle electrical system through the driver seat
wire harness.

The seat track position sensor cannot be adjusted or
repaired and, if faulty or damaged, the entire sensor
must be replaced.

OPERATION

The seat track position sensor is designed to provide a seat position data input to the Occupant Classification Mod-
ule (OCM) indicating whether the driver front seat is in a forward or rearward position. The OCM sends electronic
seat position messages to the Occupant Restraint Controller (ORC) over the Controller Area Network (CAN) data
bus. The ORC uses this data as an additional logic input for use in determining the appropriate deployment force to
be used when deploying the multistage front airbags.

The seat track position sensor receives a nominal five volt supply from the OCM. The sensor communicates the
seat position by modulating the voltage returned to the OCM on a sensor data circuit. The OCM also monitors the
condition of the sensor circuits and will store a Diagnostic Trouble Code (DTC) for any fault that is detected, then
send messages to the ORC to illuminate the airbag indicator in the instrument cluster. For proper diagnosis of the
seat track position sensor, a diagnostic scan tool is required and the appropriate diagnostic information.

REMOVAL

1. Disconnect and isolate the battery negative cable.

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 deploy-
ment, personal injury or death.

2. Reach under the front edge of the front seat cush-

ion to access the seat track position sensor (3) in a
bracket (1) located on the lower outboard seat
track (5).

3. Disconnect the electrical connector (4) from the

sensor.

4. Using a small screwdriver, depress the snap fea-

ture (2) and pull the sensor out of the bracket.

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RESTRAINTS - SERVICE INFORMATION

INSTALLATION

1. Position the seat track position sensor (3) on the

end of the bracket (1) located on the lower out-
board seat track (5).

2. Push the sensor firmly into the bracket until the

snap feature (2) locks into place.

3. Connect the electrical connector (4) to the sensor.

WARNING: Following successful completion of the
Airbag System test procedure, the Occupant Clas-
sification System Verification Test must be done
using a scan tool and the appropriate diagnostic
information.

RESTRAINTS - SERVICE INFORMATION

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