SIR System Overview

The Supplemental Inflatable Restraint (SIR) system supplements the protection offered by the occupant seat belt system (2). The SIR system has various inflator modules located throughout the vehicle, i.e. inflatable restraint steering wheel module (1), inflatable restraint IP module (1), and the inflatable restraint side impact module - LF. Each inflator module has a deployment loop that is controlled by the Inflatable Restraint Sensing And Diagnostic Module (SDM), which is mounted inside of the vehicle. The SDM performs continuous diagnostic monitoring of the SIR system electrical components. Upon detection of a circuit malfunction, the SDM will set a Diagnostic Trouble (DTC) and inform the driver by commanding the Instrument Panel Cluster (IPC) to turn the AIR BAG indicator ON.

The steering column and knee bolsters (3) are designed to absorb energy and compress during frontal collisions in order to limit leg movement and decrease the chance of injury to the driver and front passenger.