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 changes into an electrical signal. The SDM compares this electrical 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 two of the generated signals exceed the stored values, the SDM will cause current to flow through the deployment loops, deploying the air bags and/or pretensioners causing DTC B0052 to set.

Conditions for Running the DTC

Ignition 1 voltage must be within the normal operating range.

Conditions for Setting the DTC

The DTC will set if one of the following conditions occurs.

    • The SDM detects a frontal impact of sufficient force to warrant deployment of the frontal inflator modules.
    • The SDM detects a side impact of sufficient force to warrant deployment of a roof rail inflator module.
    • The SDM has deployed the seatbelt pretensioner for 3 separate deployments.

Action Taken When the DTC Sets

    • The SDM commands the AIR BAG warning lamp ON via GMLAN serial data.
    • The SDM records crash data.

Conditions for Clearing the DTC

DTC B0052 becomes a latched code after 3 consecutive pretensioner deployments or 1 frontal or side air bag deployment. You cannot clear a latched code. Replace the SDM after following the instructions in the diagnostic table.

Diagnostic Aids

The seat belt pretensioners may deploy for impacts that are not severe enough to warrant frontal or side air bag deployment. The SDM is capable of sustaining 3 pretensioner deployment events, or 1 frontal or side deployment event. After the maximum number of deployments has occurred, DTC B0052 sets and becomes a latched code, which cannot be cleared.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Important: Correct all SIR DTCs before continuing with this diagnostic table.

Use a scan tool and request the SIR DTCs.

Is there any current SIR DTC set other than DTC B0052 and B0053

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

Go to Step 3

3

If only DTC B0052 and/or B0053 are set, use a scan tool to clear codes.

Does DTC B0052 and/or B0053 clear successfully?

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 5

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5

  1. Reconnect all SIR components.
  2. Use the scan tool in order to clear the DTCs.
  3. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK