Circuit Description
The ignition switch supplies Ignition voltage to the inflatable restraint sensing and diagnostic module (SDM) at terminal A1 using the SIR Fuse. The ignition switch also supplies Ignition 1 voltage to the instrument panel cluster (IP). The AIR BAG warning indicator is controlled by the SDM via Class 2 serial data. When the ignition switch is first turned ON, the SDM responds by performing tests on the SIR system and then commanding the AIR BAG warning indicator OFF after it has flashed seven times if no trouble codes (DTCs) are found.
Diagnostic Aids
If battery voltage is outside of the normal operating voltage range, 9-16 volts, the AIR BAG warning indicator will come ON solid with no DTCs set.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: SIR Schematics | ||||
1 | Did you perform Vehicle System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the scan tool indicate that the ignition voltage is within the specified range? | 9-16 V | Go to Step 3 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
3 |
Does scan tool command the AIR BAG Warning Indicator ON then OFF? | -- | Go to Step 4 | Go to Step 5 |
4 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you complete the replacement? | -- | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | -- |
5 | The AIR BAG warning indicator is not serviceable separately. The instrument panel cluster (IPC) must be service as a complete unit. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console. Did you complete the repair? | -- | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | -- |
