GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Inflatable Restraint Sensing and Diagnostic Module (SDM) contains a sensing device that converts vehicle velocity and convert this to a electrical signal. The SDM processes the generated electrical signal and compares the signal to a value stored in memory. If the generated signal exceeds the stored value, the SDM performs additional signal processing and compares the generated signals to signals stored in memory. When two of the generated signals exceed the stored values, the SDM will cause current to flow through the inflator modules, deploying the air bags. DTC B0053 will set instead of a DTC B0051 when a deployment occurs while an inflator circuit fault is present that may result in a non-deployment situation in one or more inflator modules.

Conditions for Running the DTC

SDM must be powered up.

Conditions for Setting the DTC

SDM commands inflators deployment with loop faults present.

Action Taken When the DTC Sets

    • The SDM sets DTC B0051.
    • The SDM sets DTC B0053.
    • The SDM commands the AIR BAG warning lamp ON via Class 2 serial data.
    • The SDM records crash data.

Conditions for Clearing the DTC

DTC B0053 is a latched code. You cannot clear a latched code. Replace the SDM after following the instructions in the diagnostic table.

Diagnostic Aids

When DTC B0053 is accompanied by additional DTC(s), other than B0051, repair the malfunction causing the other DTC(s) before replacing SDM.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - SIR?

Go to Step 2

Go to Diagnostic System Check - SIR

2

  1. Turn OFF the ignition.
  2. Inspect the vehicle for any signs of air bag deployment.

Does the vehicle show any signs of air bag deployment?

Go to Step 5

Go to Step 3

3

Inspect the vehicle and undercarriage for signs of impact/collision.

Does the vehicle show any signs of impact/collision?

Go to Step 5

Go to Step 4

4

Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the replacement?

Go to Step 6

--

5

Replace all the components and perform inspections as required following an accident. Refer to Repairs and Inspections Required After a Collision .

Did you complete the appropriate inspections and necessary repairs?

Go to Step 6

--

6

  1. Reconnect all SIR components.
  2. Verify that all components, connectors, and CPAs are properly mounted.

Did you complete the repair?

Go to Diagnostic System Check - SIR

--