Chrysler 300/300 Touring/300C, Dodge Magnum. Manual - part 747

C-PILLAR MOUNTED SIDE IMPACT SENSOR

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. Remove the C-pillar trim panel (Refer to 23 -

BODY/INTERIOR/C-PILLAR TRIM - REMOVAL).

3. Disconnect the electrical connector (3).

4. Remove the two retaining screws (2).

INSTALLATION

FRONT IMPACT SENSOR

1. Position the front impact sensor in the correct

mounting location and install the two mounting
screws (2). Torque screws (2) to 7 N·m (62 in. lbs.).

2. Connect the electrical connector (3).

NOTE: If replacing the left front impact sensor, the
air intake system needs to be installed (Refer to 9
- ENGINE/AIR INTAKE SYSTEM - 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.

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RESTRAINTS - SERVICE INFORMATION

SIDE IMPACT SENSOR

B-PILLAR MOUNTED SIDE IMPACT SENSOR

1. Position the B-pillar mounted impact sensor in the

correct mounting location and install the two
mounting screws (2). Torque screws (2) to 7 N·m
(62 in. lbs.).

2. Connect the electrical connector (1).

3. Install the B-pillar trim panel (Refer to 23 - BODY/

INTERIOR/B-PILLAR TRIM - INSTALLATION).

C-PILLAR MOUNTED SIDE IMPACT SENSOR

1. Position the C-pillar mounted impact sensor in the

correct mounting location and install the two
mounting screws (2). Torque screws (2) to 7 N·m
(62 in. lbs.).

2. Connect the electrical connector (3).

3. Install the C-pillar trim panel (Refer to 23 - BODY/

INTERIOR/C-PILLAR TRIM - INSTALLATION).

RESTRAINTS - SERVICE INFORMATION

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OCCUPANT CLASSIFICATION MODULE

DESCRIPTION

The Occupant Classification Module (OCM) is secured
with two screws to a mount on the underside of the
passenger side front seat cushion frame near the out-
board front corner. Concealed within a hollow in the
center of the molded plastic OCM housing is a micro-
processor and the other electronic circuitry of the
module. The module housing is sealed to enclose and
protect the internal electronic circuitry. The OCM soft-
ware is flash programmable.

A non-calibrated OCM is available for service replace-
ment. The OCM and all of the other components of
the Occupant Classification System (OCS) including
the passenger front seat, the seat weight sensors, the
passenger or driver seat track position sensor and the
seat adjusters, cushion, back, frame, foam, springs,
and wiring harness are a factory-calibrated and
assembled unit. Any time any one of these components is removed or replaced for any reason, the OCM must be
re-calibrated using a diagnostic scan tool, the Occupant Classification Seat Weight special tool, and the Occupant
Classification System Verification Test. Refer to the appropriate diagnostic procedures.

The OCM cannot be adjusted or repaired and, if damaged or faulty, it must be replaced.

OPERATION

The microprocessor in the Occupant Classification
Module (OCM) (2) contains the Occupant Classifica-
tion 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
the diagnostic scan tool using the Controller Area Net-
work (CAN) data bus. This method of communication
is also used for OCS diagnosis and testing through
the 16-way data link connector located on the driver
side lower edge of the instrument panel.

The OCM (2) provides voltage to the four seat weight
sensors located on the corners of the passenger front
seat (1, 3, and 4), and to the seat track position sen-
sors on the outboard passenger and driver front seat
upper seat tracks. The OCM then monitors return
inputs from each of the sensors on dedicated hard
wired data communication circuits. The seat weight
sensor input allows the OCM to determine whether the
passenger side front seat is occupied and the relative
size of the occupant by providing a weight-sensing reference to the load on the seat. The seat track position sensor
provides an additional logic input to the OCM microprocessor that allows it to determine the position of the front seat
passenger and driver relative to the front airbags.

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RESTRAINTS - SERVICE INFORMATION

Pre-programmed decision algorithms and OCS cali-
bration allow the OCM microprocessor to determine
when passenger airbag protection is appropriate
based upon the seat load as signaled by the seat
weight sensors. When the programmed conditions are
met, the OCM sends the proper electronic occupant
classification messages over the CAN data bus to the
Occupant Restraint Controller (ORC), and the ORC
enables or disables the deployment circuits for the
passenger front supplemental restraints. The ORC
also provides a control output for the Passenger Airbag Disabled (PAD) Indicator in the instrument panel based
upon the electronic occupant classification messages it receives from the OCM.

The OCM also sends electronic driver and passenger seat track position messages to the ORC over the CAN data
bus. The ORC uses the seat track position data as an additional logic input for determining the force level with
which to deploy the multistage front airbags.

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 appropriate electronic messages to the ORC over the CAN data bus. Then the ORC
sets a DTC and sends messages to control the airbag indicator operation accordingly. An active fault only remains
for the duration of the fault, or in some cases for the duration 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 forever.

The OCM receives battery current on a fused ignition switch output (run-start) circuit. The OCM receives ground
through a ground circuit and take out of the body wire harness. These connections allow the OCM to be operational
whenever the ignition switch is in the Start or On positions.

The most reliable, efficient, and accurate means to diagnose the OCM, the CAN data bus network, and the elec-
tronic message inputs to and outputs from the OCM requires the use of a diagnostic scan tool and the appropriate
diagnostic information.

REMOVAL

WARNING: Never replace both the Occupant Restraint Controller (ORC) and the Occupant Classification
Module (OCM) at the same time. If both require replacement, replace one, then perform the Airbag System
test (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS 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.

RESTRAINTS - SERVICE INFORMATION

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