GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Holden 🢒 2008 🢒 Epica 🢒 Body Systems 🢒 Fixed and Moveable Windows 🢒 DTC B1476

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 Descriptor

DTC B1476: Left Roof Rail Deployment Loop Short to Battery

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

LH Roof Rail High Circuit

B1475

B1473

B1473

B1476

B1474

LH Roof Rail Low Circuit

B1475

B1473

B1473

B1476

B1474

Circuit/System Description

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the LH roof rail. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the LH roof rail connector which will short together both LH roof rail high and low circuits when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The LH roof rail high and/or low circuit is shorted to voltage.

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 255 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

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

       • The roof rail module
       • The SDM module
       • The SDM wiring harness connector

  1. Ignition OFF, disconnect the LH roof rail in-line connector.
  2. Disconnect the SDM connector. Refer to SDM replacement in Repair Instructions for connector location.
  3. Test the high and low circuits between the SDM and LH roof rail for a short to voltage. Verify that a short to voltage does not exist.
    4. ⇒If the above condition is found make the appropriate repair.
  4. If all circuits test normal then replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Inflatable Restraint Roof Side Rail Module Replacement
    •  Control Module References for SDM replacement, setup, and programming