Air Bag Indicator Circuit Malfunction

Air Bag Indicator Circuit Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

Circuit/System Description

When the ignition is turned ON, the instrument panel cluster (IPC) flashes the AIRBAG indicator 7 times for a bulb check. The inflatable restraint sensing and diagnostic module (SDM) performs diagnostic tests on the SIR system during the bulb check. If any malfunction exists the SDM will request the IPC to illuminate the AIRBAG indicator steady, via serial data. If a preexisting malfunction exists, the AIRBAG indicator will illuminate steady immediately after the ignition is turned ON. If the ignition 1 voltage is outside of the normal operating voltage range 9-16 volts, the SDM will command the IPC to illuminate the AIRBAG indicator with no DTCs present, then disables all deployment loops.

Reference Information
Schematic Reference

SIR Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

SIR System Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Diagnostic Aids

A DTC B1370 may set if the ignition 1 circuit is outside the 9-16 volts range.

Circuit/System Testing

1. Ignition ON, observe the function of the air bag indicator lamp, the indicator lamp will flash 7 times and turn OFF.

• If the air bag indicator continuously illuminates, check the serial data signal circuit for a short to ground or an open/high resistance.
• If the air bag indicator continually flashes, program the SDM.

2. Command the IPC indicators ON and OFF with a scan tool, all IPC indicators including the air bag indicator should turn ON and OFF while changing between the commanded states.

• If the air bag indicator does not illuminate, replace the IPC.

3. If all tests are normal, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* SIR/SRS Wiring Repairs (Component Tests and General Diagnostics)
* Control Module References (Programming and Relearning) for IPC and SDM replacement, setup, and programming