R024

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
When the ignition switch is turned "ON," the SDM will perform tests to diagnose critical malfunctions within itself. Upon passing these tests "Ignition 1," 36 VLR and deployment loop voltages are measured to ensure they are within their respective normal voltage ranges. The SDM monitors the voltages at "Driver Side Low" terminal "A2" and "Passenger Side Low" terminal "A5" to detect shorts to ground in the inflator module circuits.

DTC WILL SET WHEN
The 36 VLR power supply in the SDM is in its normal operating voltage range and at least one of the two inflator modules is not open. Then the voltage measured at "Driver Side Low" and "Passenger Side Low" is below a specified value for 500 milliseconds. This test is run during "Turn-ON" tests and every 100 milliseconds during "Continuous Monitoring.

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

DTC WILL CLEAR WHEN
The voltage measured at "Driver Side Low" and the voltage measured at "Passenger Side Low" are above a specified value for 500 milliseconds.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test determines whether the malfunction is occurring in the driver inflator module circuitry.
2. This test determines whether the malfunction is occurring in the passenger inflator module circuitry.
3. This test checks for a short from "Driver Side High" to ground.
4. This test checks for a short from "Driver Side Low" to ground.
5. This test checks for a short from "Passenger Side Low " to ground.
6. This test checks for a short from "Passenger Side High " to ground.

DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a short to ground in the inflator module circuits. Inspect CKTs 347, 348, 1403 and 1404 carefully for cutting or chafing. If the wiring pigtail of the SIR coil assembly, driver inflator module or passenger inflator module is darnaged the component must be replaced.