Air Bag Indicator Always On

Air Bag Indicator Always On

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

The ignition switch supplies battery voltage to the AIR BAG indicator using the AM2 fuse. The AIR BAG indicator is connected to the AIR BAG indicator control circuit of the sensing and diagnostic module (SDM). When the ignition switch is first turned to the ON position, the SDM responds by illuminating the AIR BAG indicator for approximately 6 seconds while performing diagnostic tests on the SIR system.

Reference Information
Schematic Reference

SIR Schematics ([1][2]Air Bag Systems)
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

Circuit/System Testing

1. Ignition OFF, disconnect the SDM connector.
2. Turn the ignition ON, check for 8-16V at the SDM terminal 21 while operating the wipers, headlights and rear defogger.

• If the voltage is not as specified, repair open, high resistance in the circuit.

3. Check for less than 1 ohm between the SDM terminals 25, 26 and a known good ground.

• If the resistance is not as specified, repair open, high resistance in the circuit.

4. Ignition OFF, disconnect the IPC connector.
5. Check for 11-14V volt between terminals 32, 33 and a known good ground.

• If the voltage is not as specified, repair open, high resistance in the circuit.

6. Check for less than 1 ohm between the IPC terminal 30 and a known good ground.

• If the resistance is not as specified, repair open, high resistance in the circuit.

7. Ignition ON, observe the function of the air bag indicator lamp, the indicator lamp will illuminate for 6 seconds, go OFF for 10 seconds, then remain ON.

• If the air bag indicator operates as specified, replace the SDM.
• If the air bag indicator does not operate as specified, replace the IPC.

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 SDM and IPC replacement, setup, and programming