Circuit/System Description

WARNING: This page is about a different car, the 2010 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the side impact module. A shorting bar is located in the electrical connector of the side impact module. The side impact module high control circuit and low control circuit are shorted together by the shorting bar when the electrical connector is disconnected. The shorting bar helps to prevent unwanted deployment of the inflator module during servicing.

The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If the result of any deployment loop circuit test is below specification, DTC B0021 and the appropriate symptom byte sets.