GM Service Manual Online
For 1990-2009 cars only

Circuit Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.

These test ignition and deployment loop voltages are measured to ensure that they are within their normal voltage ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deploy loops.

Each seat belt switch is cyclic monitored. The time of the buckle status change is 2 seconds. When the SDM cannot define the buckle status for 25 cycles, the SDM recognizes that the buckle is not stable and generates a buckle status settle fault.

Conditions for Setting the DTC

The passenger seat belt switch is inoperative.

Step

Action

Yes

No

Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section.

Caution: Refer to SRS Sensing and Diagnostic Module Handling Caution in the Preface section.

 

1

  1. Confirm the ignition switch is OFF and the sensing and diagnostic module (SDM) fuse has been removed.
  2. Wait for 1 minute to discharge the SDM charger.

Has the SDM discharged?

Go to Step 2

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2

Visually inspect the connector and the wiring of the passenger seat belt switch.

Is the passenger seat belt switch wiring damaged?

Go to Step 3

Go to Step 4

3

Replace the air bag wiring.

Is the repair complete?

Go to Diagnostic System Check - SIR

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4

Replace the passenger buckle assembly.

Is the repair complete?

Go to Diagnostic System Check - SIR

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