Functional Description - Occupant Detection
| 1 - Occupant Classification Module (OCM) - (IF EQUIPPED) | 2 - Driver Presence Detection Module (DPDM) - (IF EQUIPPED) |
| 3 - Passenger Airbag ON/OFF Indicator (EMEA) -or- Passenger Airbag OFF Indicator (NAFTA) | 4 - Right Seat Track Position Sensor (STPS) |
| 5 - Occupant Restraint Controller (ORC) | 6 - Left Seat Track Position Sensor (STPS) |
| 7 - Rear Right Occupant Classification Module (OCM) - (IF EQUIPPED) | 8 - Rear Center Occupant Classification Module (OCM) - (IF EQUIPPED) |
| 9- Rear Left Occupant Classification Module (OCM) - (IF EQUIPPED) |
| 1 - Rear Occupant Detection Sensors (ODS) - (IF EQUIPPED) |
| 2 - Front Left Occupant Detection Sensors (ODS) - (IF EQUIPPED) |
| 3 - Front Right Occupant Detection Sensors (ODS) - (IF EQUIPPED) |
Passenger Airbag ON/OFF Indicator (EMEA)
Vehicles manufactured for EMEA markets have a passenger airbag ON/OFF indicator integral to the Sport bar above the rearview mirror.
The text PASSENGER AIRBAG appears in the bezel just above the rearview mirror. The text ON and OFF, each beside an International Control and Display Symbol icon, are stencil-like cutouts in the opaque overlay within the indicator. The dark outer lens prevents the text and icon of the indicator from being clearly visible when it is not illuminated. Dedicated LED units behind the lens and each overlay causes the text and icon to appear in amber through the translucent lens when the indicator is illuminated from behind by the LED.
The PAB ON/OFF indicator gives an indication when the passenger seat is occupied and the PAB and seat belt tensioner deployment circuits are enabled or disabled by the ORC. This indicator is controlled by a transistor within the ORC through hardwired outputs based upon electronic passenger airbag status request messages received by the ORC from the IPC over the CAN data bus. The IPC messages to the ORC are based upon the status of a setup routine performed through the IPC by the vehicle operator.
The PAB ON/OFF indicator Light Emitting Diode (LED) units are completely controlled by the ORC. The LED units receive a battery current input on a fused ignition output (RUN) circuit. Therefore, the LED units will always be OFF when the status of the ignition is anything except ON. The LED units only illuminate when they are provided a path to ground by the ORC transistor. The IPC will request the ORC to turn ON the PAB ON/OFF indicators for the following reasons:
- Bulb Test - Each time the status of the ignition transitions to ON the PAB ON/OFF indicators are illuminated for about eight seconds.
- Passenger AirBag Disabled - Each time the ORC receives an electronic message from the IPC indicating the setup routine has requested the PAB be disabled, the PAB and seat belt tensioner deployment circuits are deactivated and the PAB OFF indicator will be illuminated. The indicator remains illuminated until the ORC receives an electronic message from the IPC indicating the setup routine has requested the PAB be enabled, or until the status of the ignition transitions to OFF, whichever occurs first.
- Passenger AirBag Enabled - Each time the ORC receives an electronic message from the IPC indicating the setup routine has requested the PAB be enabled, the PAB and seat belt tensioner deployment circuits are activated and the PAB ON indicator will be illuminated. The indicator remains illuminated until the ORC receives an electronic message from the IPC indicating the setup routine has requested the PAB be disabled, or until the status of the ignition transitions to OFF, whichever occurs first.
- Communication Error - If the ORC receives invalid messages or no messages from the IPC the PAB ON/OFF indicator status remains as it was when the last valid message was received. The ORC will also maintain the PAB deployment status as it was when the last valid message was received. The ORC and IPC will set a DTC and will illuminate the airbag indicator in the IPC when a communication error has been detected. The PAB indicator remains illuminated in the current status until the ORC receives a valid message from the IPC, or until the status of the ignition transitions to OFF, whichever occurs first.
The ORC continually monitors the messages from the IPC to decide whether the PAB and seat belt tensioner deployment circuits should be activated or deactivated. The IPC provides the proper messages to the ORC, and the ORC provides the proper control output to turn the appropriate PAB ON/OFF indicator ON.
The PAB ON/OFF indicator cannot be repaired or adjusted and, if ineffective or damaged the A/C heater control must be replaced. Refer to CONTROL, A/C AND HEATER, REMOVAL AND INSTALLATION .
Passenger Airbag OFF Indicator (NAFTA)
Vehicles manufactured for NAFTA markets have a passenger airbag OFF indicator integral to the bezel in the Sport bar above the rearview mirror.
The text PASSENGER AIRBAG appears on a lens in the Sport bar bezel just above the rearview mirror. The text OFF using an International Control and Display Symbol icon, are stencil-like cutouts in the opaque overlay within the indicator. The dark outer lens prevents the text and icon of the indicator from being clearly visible when it is not illuminated. Dedicated LED units behind the lens and each overlay causes the text and icon to appear in amber through the translucent lens when the indicator is illuminated from behind by the LED.
The PAB OFF indicator gives an indication when the passenger seat is occupied and the PAB and seat belt tensioner deployment circuits are disabled by the ORC from information sent by the OCM. This indicator is controlled by a transistor within the ORC through hardwired outputs based upon passenger occupant classification status request messages received by the ORC from the OCM over the CAN data bus. The OCM passenger classification messages to the ORC are based upon the weight status of the occupant in the passenger seat.
The PAB OFF indicator Light Emitting Diode (LED) units are completely controlled by the ORC. The LED units receive a battery current input on a fused ignition output (RUN) circuit. Therefore, the LED units will always be OFF when the status of the ignition is anything except ON. The LED units only illuminate when they are provided a path to ground by the ORC transistor. The OCM will request the ORC to turn ON the PAB OFF indicators for the following reasons:
- Bulb Test - Each time the status of the ignition transitions to ON the PAB OFF indicator is illuminated for about eight seconds.
- Passenger AirBag Disabled - Each time the ORC receives an electronic message from the OCM indicating the passenger occupant classification is less than a fifth percentile occupant or Rear Facing Infant Seat (RFIS), the PAB and seat belt tensioner deployment circuits are deactivated and the PAB OFF indicator will be illuminated. The indicator remains illuminated until the ORC receives an electronic message from the OCM indicating passenger occupant classification is not a fifth percentile occupant or RFIS, enabling the PAB or until the status of the ignition transitions to OFF, whichever occurs first.
- Communication Error - If the ORC receives invalid messages or no messages from the OCM the PAB OFF indicator status remains as it was when the last valid message was received. The ORC will also maintain the PAB deployment status as it was when the last valid message was received. The ORC and OCM will set a DTC and will illuminate the airbag indicator in the IPC when a communication error has been detected. The PAB indicator remains illuminated in the current status until the ORC receives a valid message from the OCM, or until the status of the ignition transitions to OFF, whichever occurs first.
The ORC continually monitors the messages from the OCM to decide whether the PAB and seat belt tensioner deployment circuits should be activated or deactivated. The OCM provides the proper messages to the ORC, and the ORC provides the proper control output to turn the PAB OFF indicator ON.
The PAB OFF indicator cannot be repaired or adjusted and, if ineffective or damaged it must be replaced.
Seat Track Position Sensor (STPS)
Vehicles manufactured for NAFTA markets have a STPS located on the inboard side of one of the upper seat adjuster tracks on both the driver and the passenger front seats.
The STPS for each front seat, is a hall-effect sensor designed to provide seat position data to the ORC indicating whether the driver or passenger side front seat is in a full forward or a not full forward position. The ORC uses the seat guide input as a factor in determining the appropriate force to be used when deploying the multistage driver or passenger airbag.
The STPS is designed to provide a seat position data input to the ORC indicating whether the driver or passenger front seat is in a full forward or a not full forward position. 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 DAB and PAB.
The STPS receives a nominal five volt supply from the ORC. The STPS communicates the seat position by modulating the voltage returned to the ORC on a sensor data circuit. The ORC also monitors the condition of the STPS circuits and will store a DTC for any fault that is detected. The ORC then sends messages over the CAN data bus to control the illumination of the airbag indicator in the IPC.
The STPS cannot be adjusted or repaired and, if ineffective or damaged, the entire STPS unit must be replaced.
Front Occupant Detection Sensor (ODS)
All international released vehicles are equipped with an ODS. The ODS is located on the bottom of the seat cushion foam of the passenger side front seat and each seating position in the second row. The ODS is a resistive pressure switch. The ODS closes when a pre-programmed load is placed on the seat. The ODS is used to trigger a seat belt reminder if a passenger is detected on the seat. The ODS does not affect the level of airbag deployment.
The ODS acts as a simple switch to detect loads placed upon the passenger side front seat cushion. The sensor circuits are connected to and monitored by the ORC whenever the status of the ignition is ON. The ORC uses an algorithm logic in monitoring the changing states of the sensor input to determine whether the seat cushion load is static or dynamic.
The ORC microcontroller continuously monitors all of the SRS electrical circuits to determine the system status and readiness. If the ORC detects a monitored system fault, it sets a DTC. However, because the ODS input is only used for control of the passenger belt alert feature, which has no effect on SRS component features or functions, the airbag indicator is NOT illuminated in response to a detected ODS circuit fault.
The ODS receives source current and a clean ground through dedicated sensor plus and minus circuits from the ORC. The ORC then sends the appropriate sensor status information over the CAN data bus to the IPC, which uses this information as an additional logic input used for control of the seat belt indicator and the passenger belt alert feature.
The ODS cannot be adjusted or repaired, and must be replaced if damaged or ineffective.
Rear Occupant Detection Sensor (ODS)
For EMEA markets, all rear seating positions, whether two or three, are equipped with ODS which enables the ORC to determine if a rear seat is occupied. If the seat is occupied and the seat belt has not been buckled, the seat belt reminder for the occupied rear seat is illuminated in the IPC.
The ODS is located on the bottom of the seat cushion foam of each seating position in the second row. The ODS is a resistive pressure switch. The ODS closes when a pre-programmed load is placed on the seat. The ODS is used to trigger a seat belt reminder if a rear seat passenger is detected on the seat. The ODS does not affect the level of airbag deployment.
The ODS acts as a simple switch to detect loads placed upon the passenger side front seat cushion. The sensor circuits are connected to and monitored by the ORC whenever the status of the ignition is ON. The ORC uses an algorithm logic in monitoring the changing states of the sensor input to determine whether the seat cushion load is static or dynamic.
The ORC microcontroller continuously monitors all of the SRS electrical circuits to determine the system status and readiness. If the ORC detects a monitored system fault, it sets a DTC. However, because the ODS input is only used for control of the passenger belt alert feature, which has no effect on SRS component features or functions, the airbag indicator is NOT illuminated in response to a detected ODS circuit fault.
The ODS receives source current and a clean ground through dedicated sensor plus and minus circuits from the ORC. The ORC then sends the appropriate sensor status information over the CAN data bus to the IPC, which uses this information as an additional logic input used for control of the seat belt indicator and the passenger belt alert feature.
The ODS cannot be adjusted or repaired, and must be replaced if damaged or ineffective.
Occupant Classification Module (OCM)
For information about the OCM. Refer to MODULE, OCCUPANT CLASSIFICATION (OCM), DESCRIPTION AND OPERATION .
Driver Presence Detection Module (DPDM)
For information about the DPDM. Refer to MODULE, DRIVER PRESENCE DETECTION (DPDM), DESCRIPTION AND OPERATION .