As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A CARGO FIRE WARNING LIGHT ILLUMINATED AT FL 330 WHILE EN ROUTE FROM PHX TO IAH. BOTH FIRE BOTTLES WERE DISCHARGED IAW QRH PROCEDURES AND THE FLIGHT WAS DIVERTED TO AUS WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND NO EVIDENCE OF FIRE. TROUBLESHOOTING FOUND THE COCKPIT FIRE SUPPRESSION PANEL AT FAULT. THE PANEL WAS REMOVED AND REPLACED IAW MM 26-23-10. IN ADDITION, BOTH FIRE BOTTLES WERE REMOVED AND REPLACED. SYSTEM FUNCTIONAL TESTS CHECKED GOOD IAW MM 26-23-10.