What was found
THE AFT CARGO COMPARTMENT FIRE WARNING LIGHT ILLUMINATED WHILE EN ROUTE TO IAH FROM ATL. BOTH FIRE BOTTLES WERE DISCHARGED AND THE AIRCRAFT WAS DIVERTED TO BHM WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND NO EVIDENCE OF FIRE. MAINTENANCE WAS UNABLE TO DUPLICATE THE FAILURE. THE AFT CARGO COMPARTMENT B3 FIRELOOP WAS REMOVED AND REPLACED IAW MM 26-16-10 AND GROUNDS TO ALL THREE DETECTORS WERE CLEANED. IN ADDITION, THE FIRE SUPRESSION CONTROL PANEL WAS REPLACED IAW MM 26-23-10 DUE TO FAILING PRESS TO TEST. BOTH FIRE BOTTLES, DIVERTER VALVE, METERING VALVE, AND FILTERS WERE REMOVED AND REPLACED IAW MM 26-23-10.