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 changes in vehicle velocity to an electrical signal. The SDM compares this signal to a value stored in memory. When the generated signal exceeds the stored value, the SDM performs additional signal processing and compares the generated signals to values stored in memory. When 2 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 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 of the inflator modules.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B0053 Deployment Commanded with Loop DTCs Present

Conditions for Running the DTC

The SDM must be powered up.

Conditions for Setting the DTC

Ignition voltage must be present and the SDM must have commanded an air bag deployment with loop faults.

Action Taken When the DTC Sets

    • The SDM commands ON the AIR BAG warning lamp 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 following diagnostic table.

Diagnostic Aids

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

Step

Action

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

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

Does the vehicle exhibit any signs of air bag deployment?

Go to Step 5

Go to Step 3

3

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

Does the vehicle exhibit any signs of impact or collision?

Go to Step 5

Go to Step 4

4

Replace the sensing and diagnostic module (SDM). Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 6

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5

Replace all 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

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6

  1. Reconnect all SIR system components.
  2. Verify that all components, connectors, and connector position assurances (CPAs) are properly mounted.

Did you complete the repair?

Go to Diagnostic System Check - Vehicle

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