GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using the diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B1346 : Driver Frontal Deployment Loop Stage 1 Resistance Above Threshold

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Steering Wheel Module Stage 1 High Circuit

B1348

B1346

B1346

B1349

B1347

Steering Wheel Module Stage 1 Low Circuit

B1348

B1346

B1346

B1349

B1347

Circuit/System Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform turn-on test to diagnose critical malfunctions within SDM itself.

Upon passing these tests, ignition and deployment loop voltages are measured to ensure that they are within their normal voltage ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deployment loops.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The steering wheel module deployment loop resistance is more than 4.24 ohms for 120 milliseconds.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

Conditions for Clearing the DTC

    • 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 100 malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing

    Note: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

       • The steering wheel coil module
       • The SDM module
       • The steering wheel coil module wiring harness connector
       • The SDM wiring harness connector

  1. Ignition OFF, disconnect steering wheel module and steering wheel module coil connector.
  2. Test the high and low circuits between the steering wheel module coil connector and the steering wheel module connector for a short to voltage, short to ground, or open/low resistance. Verify that a short to voltage, short to ground, or open/low resistance does not exist.
  3. If any of the above conditions are present, replace the steering wheel module coil.
  4. Ignition OFF, disconnect the SDM connector.
  5. Test the high and low circuits between the SDM and steering wheel module coil connector for a short to voltage, short to ground, or open/low resistance. Verify that a short to voltage, short to ground, or open/low resistance does not exist.
  6. If any of the above conditions are found make the appropriate repair.
  7. If all circuits test normal then replace the SDM. Refer to SDM replacement in Repair Instructions for connector location.
  8. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B1346 is set as history.
  9. If DTC B1346 is current replace the steering wheel module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Steering Wheel Inflatable Restraint Module Coil Replacement
    •  Steering Wheel Inflatable Restraint Module Replacement
    •  Control Module References for SDM replacement, setup, and programming