Chart A SDM Integrity Check

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
When the SDM recognizes "Ignition 1" voltage, applied to terminal A10 is greater than approximately 9 volts, the AIR BAG telltale 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 SDM sets an active diagnostic trouble code and illuminates the AIR BAG telltale lamp. At power-up with the existing current DTC code, the AIR BAG telltale lamp will flash more than seven times and then remain on steady. The SDM 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 B1018, B1024, B1051, B1053 and B1071. If any of these DTCs are set, the SDM must be replaced.

CHART TEST DESCRIPTION
The numbers below refer to the step numbers listed on the diagnostic chart.

Step 1. This step verifies that the fault is still occurring.
Step 2. This step verifies that the trouble codes have not changed.
Step 3. This test checks if codes reset after being cleared.

CAUTION: BE CAREFUL WHEN YOU HANDLE A SENSING AND DIAGNOSTIC MODULE (SDM). DO NOT STRIKE OR JOLT THE SDM. BEFORE APPLYING POWER TO THE SDM:

- REMOVE ANY DIRT, GREASE, ETC. FROM THE MOUNTING SURFACE.
- POSITION THE SDM HORIZONTALLY ON THE MOUNTING SURFACE.
- POINT THE ARROW ON THE SDM TOWARDS THE FRONT OF THE VEHICLE.
- TIGHTEN ALL OF THE SDM FASTENERS AND SDM BRACKET FASTENERS TO THE SPECIFIED TORQUE VALUE.

FAILURE TO FOLLOW THE CORRECT PROCEDURES COULD CAUSE AIR BAG DEPLOYMENT, PERSONAL INJURY OR UNNECESSARY SIR SYSTEM REPAIRS.

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 DTC remains current, the following diagnostic procedures must be performed to verify the need for SDM replacement.

NOTICE: Perform "SIR DIAGNOSTIC SYSTEM CHECK" before proceeding with this chart. SIR Diagnostic System Check