Observe the bulb check
Factory operation flashes the AIR BAG indicator during startup while the SDM performs diagnostics. A lamp that stays on requires diagnosis.
SIR · 2002 · SAFETY SYSTEM
2002 Firebird AIR BAG Warning Light Diagnosis
Treat an AIR BAG warning as a diagnostic-system fault, not a part name. Use SIR codes and the factory safety procedure.
APPLICATION: 2002 Pontiac Firebird / Formula / Trans Am. Configuration-specific equipment must match the vehicle before applying a circuit path.
Scan the SIR system
Retrieve SIR DTCs with appropriate equipment. Loss of communication and abnormal ignition voltage can also illuminate the warning.
Check system voltage first
The factory symptom path recognizes out-of-range Ignition 1 voltage as a possible cause. Resolve obvious vehicle-voltage problems before condemning SIR modules.
STOP — SIR SERVICE PRECAUTIONS
Airbag deployment circuits can retain reserve energy after power is removed. Do not use ordinary probing, jumper wires or resistance checks on deployment circuits. Follow the exact GM disabling/enabling procedure.
FPV RULE
OBSERVE → MEASURE → ISOLATE → PROVE → REPAIR → VERIFY. A symptom or DTC is a starting point, not a parts verdict.