If a malfunction is detected, a DTC will be stored in non-volatile memory. 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 LF side module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the LF side module connector which will short together both LF side module high and low circuits when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

The LF side module deployment loop resistance is more than 3.54 ohms.

The SDM commands the AIR BAG indicator ON.

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Important: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

•	The side module

•	The SDM module

•	The SDM wiring harness connector

1. Ignition OFF, disconnect LF side module in-line connector.
2. Disconnect the SDM connector. Refer to SDM replacement in Repair Instructions for connector location.
3. Test the high and low circuits between the SDM and LF side module for a open/high resistance. Verify that a open/high resistance does not exist.

⇒	If the above condition is found make the appropriate repair.

4. If all circuits test normal then replace the SDM.
5. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B1378 is set current.

⇒	Replace the LF side module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.