When the ignition is turned ON, the instrument panel cluster (IPC) flashes the air bag indicator 7 times for a bulb check. The inflatable restraint sensing and diagnostic module (SDM) performs diagnostic tests on the SIR system during the bulb check. If any malfunction exists the SDM will request the IPC to illuminate the air bag indicator steady, via serial data. If a preexisting malfunction exists, the air bag indicator will illuminate steady immediately after the ignition is turned ON. If the ignition 1 voltage is outside of the normal operating voltage range 9-16 volts, the SDM will command the IPC to turn the air bag indicator ON with no DTCs present, then disables all deployment loops.

A DTC B1370 may set if the ignition 1 circuit is outside the 9-16 volts range.

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

SIR System Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, with a scan tool, verify the Battery Voltage Parameter is within 9-16 volts.

⇒	If not the specified range, refer to Diagnostic System Check - Vehicle.

2. Cycle the key from OFF to ON, and monitor the IPC. The SIR warning indicator should flash then turn OFF.

⇒	If the SIR warning indicator continually flashes, reprogram the SDM.

3. With a scan tool, perform the display test to command the IPC indicators ON then OFF. The Air Bag indicator should cycle between the commanded states.

⇒	If the Air Bag indicator does not cycle between the commanded states, replace the IPC.

4. If tests are normal, replace the SDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.