Chevrolet Cruze Repair Manual: Inflatable Restraint Passenger Presence Detection System - If Equipped

Note: The passenger presence detection system includes an ECU and a sensor mat that can be serviced separately. After repairing or replacing any part of the passenger presence detection system, the system must be rezeroed in order to function properly.

The passenger presence detection system is used to monitor the weight of an occupant on the front outboard passenger seat and communicate the status to the inflatable restraint sensing and diagnostic module (SDM) whether to enable or suppress the deployment of the passenger frontal air bag module. The passenger presence detection system consist of an electronic control module, sensor mat, heated seat element (if equipped), wiring harness, and PASSENGER AIR BAG ON/OFF indicators. The sensor is made up of flexible plastic material placed underneath the seat cushion foam. Pressure on the passenger presence detection mass sensor is converted into an electrical signal that the module reads and determines the passengers classification. If the sensor determines that the occupant weight is less than a specified value, the passenger presence detection module will send a suppress signal to the SDM to disable the passenger frontal air bag module. If the sensor determines the occupant weight is higher than a specified value, the passenger presence detection module will send an enable signal to the SDM to enable the passenger frontal air bag module. The passenger presence system module will notify the customer of the enable/disable status by illuminating one of the PASSENGER AIR BAG ON/OFF indicators. The passenger presence system will also notify the SDM of a fault and the SDM will request the instrument cluster to illuminate the AIR BAG indicator.

Inflatable Restraint PASSENGER AIR BAG ON/OFF Indicator - If Equipped

The PASSENGER AIR BAG ON/OFF indicators are used to notify the driver and passenger when the passenger frontal air bag module is enabled or disabled.

AIR BAG Indicator

The AIR BAG indicator, located in the instrument cluster and is used to notify the driver of SIR system malfunctions and to verify that the inflatable restraint sensing and diagnostic module (SDM) is communicating with the instrument cluster. When the ignition is turned ON, the SDM is supplied with ignition positive voltage. The SDM requests the instrument cluster will momentarily turn on the AIR BAG indicator. While the indicator is on, the SDM conducts tests on all SIR system components and circuits. If no malfunctions are detected the SDM will communicate with the instrument cluster through the serial data circuit and command the AIR BAG indicator OFF. The SDM provides continuous monitoring of the air bag circuits by conducting a sequence of checks. If a malfunction is detected the SDM will store a diagnostic trouble code (DTC) and command the instrument cluster to illuminate the AIR BAG indicator via serial data. The presence of a SIR system malfunction could result in non-deployment of the air bags or deployment in conditions less severe than intended. The AIR BAG indicator will remain ON until the malfunction has been repaired.