GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2003 🢒 ION 🢒 Steering 🢒 Steering Wheel and Column 🢒 DTC B0051

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 B0051 to set.

Important: 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 B0051 becomes a latched code, which cannot be cleared.

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 and/or pretensioners.
    • The SDM detects a side impact of sufficient force to warrant deployment of a roof rail inflator module.

Action Taken When the DTC Sets
    • 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 B0051 can be cleared if the following conditions are met.

    • Three consecutive seat belt pretensioner deployment events have not occurred
    • One frontal or side air bag deployment has not occurred.
    • The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
    • A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DTC B0051 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.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

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 signs of inflator module or pretensioner deployment.

Does the vehicle show any signs of inflator module or pretensioner deployment?

Go to Step 4

Go to Step 3

3

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

Does the vehicle show any signs of impact/collision?

Go to Step 4

Go to Step 5

4
  1. Install a scan tool.
  2. With a scan tool, observe the SIR DTC display.
  3. If a history DTC exists, refer to Diagnostic Aids for that specific DTC and diagnose the problem.
  4. Replace components and perform inspections as required following an accident. Refer to Repairs and Inspections Required After a Collision .

Did you complete the action?

Go to Step 5

--

5

Use the scan tool to attempt to Clear DTC B0051.

Has DTC B0051 been cleared successfully?

Go to Step 7

Go to Step 6

6

Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the replacement?

Go to Step 7

--

7
  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