Chart A SDM Integrity Check

Diagnostic Chart:

Circuit Schematic:

WARNING: During service procedures, be very careful when handling a sensing and diagnostic module (SDM). Never strike or jar the SDM. never power up the SIR system when the SDM is not rigidly attached to the vehicle. All SDM and mounting bracket fasteners must be carefully torqued and the arrow must be pointing toward the front of the vehicle to ensure proper operation of the SIR system. The sum could be activated when powered while not rigidly attached to the vehicle which could cause deployment and result in personal injury.



CIRCUIT DESCRIPTION
When the SDM recognizes "Ignition 1,, voltage, applied to terminal A7 is greater than approximately 6.64 volts, the AIR BAG warning lamp is flashed seven times to verify operation. During this time the SDM performs "turn-on" tests (including current source diagnostics) followed by "continuous monitoring" tests. When a malfunction is detected the ADM sets an active diagnostic trouble code and illuminates the AIR BAG warning lamp. At power-up with the existing current code, the AIR BAG telltale will flash more than seven times and then remain on steady. The ADM will clear active diagnostic trouble codes and move them to a history file when a malfunction is no longer detected and/or the ignition switch is cycled, except for DTC 51, 52, and 71. DTC 51 can only be cleared using a Saturn Portable Diagnostic (Scan) (PDT) Tool "Clear Codes" command. DTC 52 will become a history code if the crash data area is full and the "Clear Codes" command is sent. The history DTC 52 can not be cleared. DTC 71 may not clear after a "Clear Codes" command is sent.

CHART TEST DESCRIPTION
The numbers below refer to the step numbers listed on the diagnostic chart.
1. This step verifies that the fault is still occuring.
2. This step verifies that the trouble codes have not changed.
3. This test checks if codes reset after being cleared.





CHART A
This chart assumes that the "SIR Diagnostic System Check" and either a symptom chart or a diagnostic trouble code chart diagnosis have been performed. When all circuitry outside the SDM has been found to operate properly, as indicated by the appropriate diagnostic chart, and the symptom or code remains current, the following diagnostic procedures must be performed to verify the need for SDM replacement.