Air Bag Control Module: Description and Operation

SENSING AND DIAGNOSTIC MODULE (SDM)

CAUTION: Refer to Sensing and Diagnostic Module Handling Caution in Service Precautions.




The SDM is located on the floor beneath the floor console assembly. The SDM performs the following functions :
- Monitors the supplemental inflatable restraints (SIR) electrical components and sets a diagnostic trouble code (DTC) when malfunction is detected.
- Records any faults that are discovered.
- Displays SIR diagnostic trouble codes and system status information when connected to a scan tool.
- Illuminates the air bag indicator to alert the driver to any fault.
- Provides a reserve power source to deploy the air bags and pretensioners if an accident has disabled the normal power source.
- Monitors vehicle velocity changes to detect frontal impacts, which are severe enough to warrant deployment.
- Causes current to flow through the air bag modules and pretensioner to cause deployment if a frontal impact of sufficient force is detected.




The SDM contains no user-serviceable parts.