Side Impact Sensor (Sis)
WARNING: This page is about a different car, the 2002 Buick Park Avenue. However, it is still accessible from the selected car via links, so may be relevant.
SIS is located in driver-side and passenger-side lower B-pillars. Each SIS monitors vehicle acceleration and velocity changes to detect side impact collisions. SIS are not part of deployment loop, but provide input to SDM.