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.

In case of passenger side air bag inflation by side impact, the SDM maintains the warning lamp ON. All the air bag systems, including the pretensioners, the side air bag sensor, and the wiring should be replaced. If the passenger side air bag inflation by side impact counts over 5, the SDM should also be replaced.

Conditions for Setting the DTC

The history of passenger air bag inflation or belt pretensioner explosion is in the SDM.

Step

Action

Yes

No

Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section.

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

 

1

Perform the Diagnostic System Check - SIR.

Is the Diagnostic System Check - SIR complete?

Go to Step 2

Go to Diagnostic System Check - SIR

2

  1. Disconnect the negative battery cable.
  2. Wait 1 minute for the SDM capacitor to discharge.
  3. Visually inspect the supplemental inflatable restraint (SIR) wiring harness.

Is there any visible damage to the SIR harness?

Go to Step 4

Go to Step 3

3

  1. Disconnect the negative battery cable.
  2. Replace the sensing and diagnostic module (SDM).

Is the repair complete?

Go to Diagnostic System Check - SIR

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4

  1. Replace the SIR wiring harness.
  2. Reconnect the negative battery cable.

Is the repair complete?

Go to Diagnostic System Check - SIR

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