Circuit Description
The inflatable restraint Sensing and Diagnostic and Seat Belt Pretensioner Module (SDM) performs tests to diagnose critical malfunctions within itself when the ignition switch is turned ON. The SDM monitors the firing loops to detect leakage currents to ground and system voltage in the air bag inflator module and seat belt pretensioner circuits. The deployment loop resistances are measured to ensure they are within their respective normal resistance ranges. The SDM then goes into a Continouos Monitoring mode. The SDM service wait time is 1 minute. Refer to On-Vehicle Service for enable/disable procedures.
Conditions for Setting the DTC
The SDM is installed in the vehicle in a unconfigured state. A replacement SDM must be programmed by the technician using a scan tool. This malfunction is detected asynchronously when the IGNITION voltage is above a specified value.
Action Taken When the DTC Sets
| • | The SDM sets a diagnostic trouble code. |
| • | The SDM turns ON the AIR BAG warning lamp. |
Conditions for Clearing the DTC
The Serial Data configuration programming via the scan tool is successful.
Test Description
An example test description follows:
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Does the SDM Configuration show the specified value? | SDM Not Config. | Go to Integrity Check | ||
3 | DTC 52 indicates that the inflatable restraint Sensing and Diagnostic and Seat Belt Pretensioner Module (SDM) is not programmed for use in this vehicle. Refer to the Programming option on the scan tool Supplemental Inflatable Restraint main menu. Is the SDM reprogrammed? | -- | -- |
