Air Bag Indicator Circuit Malfunction

Air Bag Indicator Circuit Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

When the ignition is turned ON, the instrument cluster flashes the SIR Air Bag warning indicator 7 times for a bulb check. The inflatable restraint sensing and diagnostic module performs diagnostic tests on the SIR system during the bulb check. If any malfunction exists the inflatable restraint sensing and diagnostic module will request the instrument cluster to illuminate the air bag warning indicator steady, via serial data. If a preexisting malfunction exists, the air bag warning 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 inflatable restraint sensing and diagnostic module will command the instrument panel cluster to illuminate the air bag warning indicator with no DTCs present, then disables all deployment loops.

Diagnostic Aids

* If the ignition 1 voltage for the inflatable restraint sensing and diagnostic module is outside of the normal operating voltage range, 9-16 volts, the air bag warning indicator will continuously illuminate and no DTC will set.

* The loss of serial data communication between the inflatable restraint sensing and diagnostic module and the instrument panel cluster will cause the air bag warning indicator to continuously illuminate.

Reference Information

Schematic Reference

SIR Schematics [1][2]Air Bag Systems

Connector End View Reference

Component Connector End Views Sunshade - Left (DH6)

Description and Operation

SIR System Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Testing

1. Ignition ON, with a scan tool, verify the Battery Voltage Signal Parameter is 9-16 volts.

• If not the specified range, refer to Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle.

2. Ignition OFF, observe the SIR Air Bag warning indicator while turning the ignition ON. The SIR warning indicator should flash 7 times and then turn OFF.

• If the SIR warning indicator continually flashes, program the K36 inflatable restraint sensing and diagnostic module.

• If the SIR warning indicator remains on steady, test for Current DTCs. Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

3. Ignition ON, with a scan tool command the P16 instrument cluster indicators ON and OFF. The Air Bag indicator should turn ON and OFF when changing between the commanded states.

• If the air bag indicator does not illuminate as expected, replace the P16 instrument cluster.

4. If all tests are normal, replace the K36 inflatable restraint sensing and diagnostic module.

Repair Instructions

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

* SIR/SRS Wiring Repairs SIR/SRS Wiring Repairs

* Control Module References Control Module References for inflatable restraint sensing and diagnostic module or instrument cluster replacement, setup, and programming