Frontal SIR System Description

The frontal SIR system consists of the following components:
^ An inflatable restraint Sensing and Diagnostic Module (SDM).
^ An inflatable restraint steering wheel module (steering wheel air bag).
^ An Inflatable restraint steering wheel module coil.
^ An inflatable restraint IP Module (IP air bag).
^ Two inflatable restraint front end discriminating sensors
^ An AIR BAG Warning Lamp in the Instrument Panel Cluster (IPC).

The inflatable restraint sensing and diagnostic module (SDM), inflatable restraint steering wheel module coil, inflatable restraint steering wheel module, inflatable restraint IP module, and the connecting wires make up the frontal deployment loops, and front end dicriminating sensors.The function of the frontal deployment loops is to supply current through the frontal inflator modules, deploying the frontal inflator modules simultaneously. Deployment occurs when the SDM detects vehicle velocity changes severe enough to warrant deployment.

The SDM compares the input signal to a value stored in memory. When the generates signal exceeds the stored value, the SDM performs additional signal processing and compares the generates signals to values stored in memory. When two of the generated signals exceed the stored values, the SDM will cause current to flow through the frontal inflator modules deploying the frontal inflator modules.