SIR Diagnostic System Check

Wiring Diagram:

CIRCUIT DESCRIPTION
The ignition switch supplies IGNITION 1 voltage to the inflatable restraint Sensing and Diagnostic Module (SDM) at terminal 10 using the AIR BAG Fuse. When the ignition switch is first turned to the RUN position, the SDM responds by flashing the AIR BAG warning lamp seven times, then turning it OFF, while performing tests on the SIR system.

DIAGNOSTIC AIDS
Diagnosing diagnostic trouble codes in the correct order is very important. Failure to diagnose the DTCs in the order specified may result in extended diagnostic time, incorrect diagnosis and incorrect parts replacement.

TABLE TEST DESCRIPTION
1. The inflatable restraint I/P module enable switch must be in the ON position to perform the system diagnostic check.
2. The AIR BAG warning lamp should flash seven times after the ignition is first turned to the RUN position.
3. The AIR BAG warning lamp indicates improper operation. This test differentiates a warning lamp stays ON condition from a warning lamp does not come ON condition.
4. The AIR BAG warning lamp should turn OFF after flashing seven times.
5. This test checks for proper operation of the serial data line.
7. This test will identify the stored diagnostic trouble codes and whether they are current or history.
10. This test checks for the proper operation of the serial data line. This test also identifies any stored history diagnostic trouble codes.