Symptom Related Diagnostic Procedures

Diagnostic Chart:

Schematic:

CIRCUIT DESCRIPTION
The ignition switch supplies Ignition voltage to the Inflatable Restraint Sensing and Diagnostic Module (SDM) at terminal Al using the SIR (Air Bag) Fuse. The ignition switch also supplies Ignition 1 voltage to the instrument panel cluster (IPC).

The AIR BAG warning lamp 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 lamp OFF after it has flashed seven times if no DTCs are present.

DIAGNOSTIC AIDS
If battery voltage is outside of the normal operating voltage range (9 volts-16 volts), the AIR BAG warning lamp will come ON solid with no DTCs set.