Supplemental Inflatable Restraint (SIR)

Diagnostic Chart:

Circuit Schematic:

CIRCUIT DESCRIPTION
When the ignition switch is turned On, the Sensing & Diagnostics Module (SDM) will perform tests to diagnose critical malfunctions within itself. Upon passing these tests "Ignition 1," 36 VLR (Voltage Loop Energy Reserve), and deployment loop voltages are measured to ensure they are within their respective normal voltage ranges. The SDM then proceeds with the "Current Source Diagnostics." "Passenger Side Low" terminal A6 is grounded through a resistor and the passenger current source connected to "Passenger Side High" terminal As allows a known amount of current to flow. After "Current Source Diagnostics" are completed the SDM removes the low resistance ground from "Passenger Side Low" and switches the driver current source at "Passenger Side High." The SDM then measures the voltage at "Passenger Side High" and "Passenger Side Low"during "Continuous Monitoring." By monitoring the voltage difference between "Passenger Side High" and "Passenger Side Low" the ADM calculates the combined resistance of the passenger inflator module, harness wiring circuits 1403 and 1404 and connector terminal contact.

DTC WILL SET WHEN:
The voltage difference between "Passenger Side High" terminal As and "Passenger Side Low" terminal A6 is above or equal to a specified value for 500 milliseconds during "Current Source Diagnostic" or "Continuous Monitoring."

ACTION TAKEN:
SDM turns On the AIR BAG warning lamp and sets a diagnostic trouble code.

DTC WILL CLEAR WHEN:
The voltage difference between "Passenger Side High" terminal A5 and "Passenger Side Low" terminal A6 below a specified value for 500 milliseconds during "Continuous Monitoring."

DTC CHART TEST DESCRIPTION:
Number(s) below refer to step number(s) on the diagnostic chart.
1. This test determines whether the malfunction is in the passenger inflator module circuit in the ADM wiring harness circuitry.
2. This test determines whether the malfunction is due to a high resistance in circuit 1404
3. This test determines whether the malfunction is due to a high resistance in circuit 1403

DIAGNOSTIC AIDS:

An intermittent condition is likely to be caused by poor connection at the passenger inflator module harness connector terminal A and B, ADM terminals As and A6, or an open in circuit 1403 or circuit 1404.

Was the "SIR Diagnostic System Check" performed?

When measurements are requested in this chart, use (Saturn Tool) SA 91114NE DVM with correct terminal adapter from SA 9206Z.