SDM Integrity Check

Circuit Description
When the Inflatable Restraint Sensing and Diagnostic and Seat Belt Pretensioner Module (SDM) recognizes IGNITION, applied to terminal 5, is greater than 9.0 volts, the SDM flashes the AIR BAG warning lamp seven times to verify operation. At this time the SDM performs POWER-ON and CONTINUOUS MONITORING tests. The SDM sets a current diagnostic trouble code and illuminates the AIR BAG warning lamp when a malfunction is detected. The SDM clears the current diagnostic trouble codes and moves them to a history file when the malfunction is no longer detected and/or the ignition switch is cycled.

Test Description
The numbers below refer to step numbers on the diagnostic table.
1. This test confirms a current malfunction. If no current malfunction is occurring (history DTC set), refer to the diagnostic aids for the appropriate DTC table as indicated through the scan tool. Do not replace the SDM for a history DTC other than a DTC 55.
2. This test checks for a malfunction introduced into the SIR system during the diagnostic process. It is unlikely that a malfunctioning SDM would cause a new malfunction to occur during the diagnostic process.
3. When you have found all circuitry outside the SDM to operate properly, as indicated by the appropriate diagnostic table, replace the SDM.

This table assumes that the SIR Diagnostic System Check and either a symptom table or a Diagnostic Trouble Code (DTC) table diagnosis has been performed. When all circuitry outside the SDM has been found to operate properly, as indicated by the appropriate diagnostic table, and the symptom or DTC remains current, the following diagnostic procedures must be performed to verify the need for SDM replacement.