Occupant Classification Module (OCM)
REMOVAL
To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbags, airbag curtains, knee blocker, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect the Intelligent Battery Sensor (IBS)/negative battery cable assembly from the negative battery post, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.
The Occupant Classification System (OCS) is used only in the passenger side front seat of vehicles manufactured for domestic markets. Vehicles manufactured for export markets use the Occupant Detection Sensor (ODS) instead of the OCS on the passenger side front seat.
All of the components of the OCS including the Occupant Classification Module (OCM), the seat weight sensor, the plastic insulator seat weight sensor pad, the passenger seat cushion foam, the electronic pressure sensor, the OCS pressure hose, and the heat mat and vent bag (if equipped), are serviced only as a factory-calibrated and assembled unit. Any time any one of these components requires replacement for any reason, the entire calibrated OCS must be replaced and re-zeroed in the Occupant Restraint Controller (ORC) using a diagnostic scan tool. Refer to the appropriate diagnostic information.
If ONLY the seat trim requires replacing and no other components are compromised. Replace the trim and follow the OCS re-zeroing process. Refer to the appropriate diagnostic information.
- Disconnect and isolate the negative battery cable. If equipped with an Intelligent Battery Sensor (IBS), disconnect the IBS connector first before disconnecting the negative battery cable. Wait two minutes for the system capacitor to discharge before continuing service.
- Remove the passenger front seat from the vehicle. Refer to SEAT, FRONT, REMOVAL AND INSTALLATION
.
1 - OCM 2 - Blade 3 - Wire Harness Connector - Disconnect the seat wire harness connector from the OCM beneath the outboard front corner of the seat cushion pan.
- Using a small flat-bladed screwdriver or a small pick tool, carefully pry the latch tab integral to the OCM electrical receptacle to release it from the blade of the mounting bracket beneath the outboard front corner of the seat cushion.
- Remove the cover and foam seat cushion from the passenger front seat. Refer to COVER, SEAT CUSHION, FRONT, REMOVAL AND INSTALLATION
.NOTE:
If equipped with heated seats, vented seats or both, remove the heat mat and vent bag with the seat cushion.
- Remove the three push-in plastic fasteners that secure the Seat Weight Sensor (seat weight sensor) and the plastic insulator seat weight sensor pad to the seat cushion pan.
1 - Sensor Pad 2 - Seat Cushion Pan 3 -Push-In Plastic Fasteners - Remove the seat weight sensor, the pad, the pressure hose and the OCM with integral electronic pressure sensor from above the front seat cushion as a unit.
- If any of the OCS components requires replacement, discard the entire OCS unit. Replace it with the entire contents of the factory-calibrated service replacement package, which includes an OCM with integral and internal electronic pressure sensor, a pressure hose, the seat weight sensor, the plastic insulator seat weight sensor pad, the heat mat (if equipped), the vent bag (if equipped) and the seat cushion foam. NOTE:
If the vehicle is equipped with heated seats, vented seats or both, the proper OCM kit will come with these components attached to the new seat cushion foam.
INSTALLATION
Follow the removal procedure in reverse for general reassembly of the components on the vehicle. The steps listed below are calling out specific procedures that should be followed during installation.
- All of the components of the OCS including the Occupant Classification Module (OCM), the seat weight sensor, the plastic insulator seat weight sensor pad, the passenger seat cushion foam, the electronic pressure sensor, the OCS pressure hose, and the heat mat and vent bag (if equipped), are serviced only as a factory-calibrated and assembled unit. Any time any one of these components requires replacement for any reason, discard all of the removed OCS components including the OCM with integral and internal electronic pressure sensor, the pressure hose, the seat weight sensor, the plastic insulator seat weight sensor pad, the heat mat and vent bag (if equipped), and the seat cushion foam and replace them with the entire contents of the proper factory-calibrated OCS service replacement package, then re-zero the OCS in the Occupant Restraint Controller (ORC) using a diagnostic scan tool. Refer to the appropriate diagnostic information.
- Position the seat weight sensor, the plastic insulator seat weight sensor pad, the OCS pressure hose and the OCM with integral electronic pressure sensor to the top of the front seat cushion pan as a unit. Lift the back of the seat weight sensor and pad far enough to access and insert the OCM and pressure hose between the seat cushion springs to the underside of the seat cushion. Be certain the pressure hose is not pinched or kinked.
- If the vehicle is equipped with heated seats, vented seats or both, the proper OCM kit will come with these components attached to the new seat cushion foam.
- Collect ALL of the OCS components, including the seat cushion foam assembly replaced during this repair procedure. Be certain ALL parts are the original equipment parts. Return ALL removed parts to the Mopar Quality Center / QEC for root cause evaluation. If the original equipment removed parts have not ALL been replaced, return to Step 1 and complete all steps of the repair process.
- From the underside of the seat, snap the OCM to the blade of the mounting bracket beneath the outboard front corner of the seat. Route the pressure hose away from sharp or moving objects and be certain the hose is not kinked.
- Do not connect the negative battery cable at this time. The Supplemental Restraint System (SRS) Verification Test procedure should be performed following service of any SRS component. Refer to SUPPLEMENTAL RESTRAINT SYSTEM VERIFICATION TEST .
- Following successful completion of the SRS Verification Test procedure, perform the OCM System Verification Test procedure found in the diagnostic scan tool under Miscellaneous Functions. Refer to the appropriate diagnostic procedures.