SIR Diagnostic Flow

Circuit Description

The ignition switch supplies Ignition 1 voltage to the Inflatable Restraint Sensing and Diagnostic Module (SDM) at terminal A1 using the SDM Fuse. When the ignition switch is first turned to the RUN position, 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.

Diagnostic Aids

You must diagnose the diagnostic trouble codes in the order specified by the SIR diagnostic system check. Failure to do so may result in the following:

^ Extended Diagnostic Time

^ Incorrect Diagnosis

^ Incorrect Parts Replacement

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step checks to see if the AIR BAG warning lamp flashes seven times when the ignition key is turned to the RUN position.

2. This step checks to see if the SIR warning lamp turns OFF after it has flashed seven times.

3. This step checks to see if the scan tool can communicate with the Inflatable Restraint Sensing and Diagnostic Module (SDM).

4. This step checks to see if there are any current DTCs present.

6. This step checks to see if the scan tool can communicate with the SDM.

7. This step checks to see if there are any history DTCs present.