Inflatable Restraint Side Impact Sensor (SIS)

The side impact sensors (SIS) contain a sensing device which monitors vehicle acceleration and velocity changes to detect side collisions that are severe enough to warrant side inflator module deployment. Each SIS is not part of the deployment loop, but instead provides an input to the inflatable restraint sensing and diagnostic module (SDM). The SDM contains a microprocessor that performs calculations using the measured accelerations and compares these calculations to a value stored in memory. When the generated calculations exceed the stored value, the SDM will cause current to flow through the deployment loops, deploying the side air bags.