When you first turn ON the ignition, the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM) performs tests to diagnose critical malfunctions within itself. Then, the SDM proceeds with the RESISTANCE MEASUREMENT test to measure the deployment loop resistances to ensure they are within their respective normal resistance ranges. Upon passing these tests, the energy reserve is charged and the firing transistors are tested. The SDM then goes into CONTINUOUS MONITORING mode. The SDM provides input power to the inflatable restraint side impact sensor (SIS). When input power is first detected, the SIS responds by perofrming internal diagnostics. Next, the SIS sends a OK/NOK message to the SDM to indicate proper operation.

When the ignition voltage is within the normal operating voltage range, the SDM monitors the inflatable restraint side impact sensor and the circuits.

The DTC will set when an internal fault within the SIS has been detected by the SDM.

The SDM turns ON the AIR BAG warning lamp.

This DTC is an indication of an internal failure within the SIS.

The following numbers refer to the step numbers in the diagnostic table:

2. This step checks to see if either DTC 83 or DTC 84 is present.

4. This step determines if there is a malfunctioning inflatable restraint side impact sensor (SIS) or if there is a malfunctioning SDM.