For 1990-2009 cars

Important: Finish the following steps before going to the Symptom Table:

1. Perform Diagnostic System Check - Vehicle , check and verify the following conditions are met:

• | No DTC is set.

• | Inflatable Restraint Sensing and Diagnostic module (SDM) is able to communicate through the serial data link.

2. Review the SIR Description and Operation in order to familiarize yourself with the system functions. Refer to SIR System Description and Operation .

### Visual/Physical Inspection

• | Inspect for aftermarket devices which could affect the operation of the SIR system. Refer to Checking Aftermarket Accessories .

• | Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

### Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

### Symptom List

Refer to a symptom diagnostic procedure from the following list to diagnose the symptom:

• | Air Bag Indicator Circuit Malfunction

• | Passenger Presence System Indicator Circuit Malfunction