Sensing & Diagnostic Module (SDM)

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.

SDM monitors vehicle velocity changes to detect frontal or side collisions which are severe enough to warrant air bag module deployment. When a frontal collision of sufficient force is detected, SDM will deploy driver-side and passenger-side air bags. When a side collision of sufficient force is detected, SDM will deploy side impact air bag module on side of impact. SDM maintains a 23 Volt Loop Reserve (23 VLR) energy supply to provide deployment energy for up to one minute after loss of battery voltage.

Additionally, SDM provides diagnostic monitoring of SIR system electrical components. When a malfunction is detected, SDM sets a Diagnostic Trouble Code (DTC) which can be retrieved using a scan tool. SDM warns driver of SIR system malfunctions by controlling AIR BAG warning light.