Identify the pattern
Note whether every blower speed is dead, only certain speeds fail, or operation is intermittent. Those patterns point to different branches.
HVAC · 2002 · BLOWER
2002 Firebird HVAC Blower Inoperative Diagnosis
A dead blower motor is an electrical symptom. The factory service information provides separate blower-motor testing and HVAC symptom diagnosis, so start at the circuit instead of the motor.
APPLICATION: 2002 Pontiac Firebird / Formula / Trans Am with factory HVAC. Diagnose aftermarket wiring separately if installed.
Check power path and command
Use the applicable wiring diagram to verify circuit protection, switch/control output, relay/resistor path where applicable, connector condition and motor power/ground.
Prove the motor
Only condemn the blower motor after its required feed and ground are present under the failure condition and the motor still does not operate correctly.
DO NOT BUY A BLOWER MOTOR YET
Loss of selected speeds, a bad connection, control fault or power/ground problem can mimic a failed motor.
FPV RULE
OBSERVE → MEASURE → ISOLATE → PROVE → REPAIR → VERIFY. A symptom is a starting point, not a parts verdict.