The inflatable restraint side impact sensor (SIS) utilizes a unidirectional 2-wire circuit. The SIS modulates current on the interface to send ID, state of health (SOH), and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the SIS. When the ignition is turned ON and input power from the SDM is first detected, the SIS responds by performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds. The SIS continually communicates status messages to the SDM, which determines if a fault is present in the SIS circuit. When a fault is detected, the SDM resets the SIS twice by removing and reapplying power to it. If the fault is still present, the SDM will set a DTC.

Ignition voltage is between 9-16 volts.

A communication error occurs between the SDM and the driver side impact sensor.

The SDM commands the AIR BAG indicator ON.

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

•

The SIS

•	The SDM module

•	The SIS wiring harness connector

•	The SDM wiring harness connector

1. Ignition ON, use the scan tool as clear SIR codes then recheck for DTCs.

⇒	If DTC B1409 is set current, replace the driver SIS.

2. Reconnect all SIR components. Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify no DTCs are set.

⇒	If DTC B1409 is current, replace the SDM.