GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2004 🢒 Optra 🢒 Restraints 🢒 SIR 🢒 DTC 031

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.

Conditions for Setting the DTC

The SDM does not implement diagnostic operation. The wiring harness of the SDM should be inspected before replacing 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.

Did you perform the Diagnostic System Check - SIR?

Go to Step 2

Go to Diagnostic System Check - SIR

2
  1. Disconnect the negative battery cable.
  2. Wait 1 minute for the sensing and diagnostic module (SDM) capacitor to discharge.
  3. Visually inspect the supplemental inflatable restraints (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. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  2. Replace the SDM.

Did you complete the repair?

Go to Diagnostic System Check - SIR

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4
  1. Replace the SIR wiring harness.
  2. Reconnect the negative battery cable.

Did you complete the repair?

Go to Diagnostic System Check - SIR

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