What was found
THE FORWARD CARGO FIRE LIGHT AND BELL ACTIVATED WHILE EN ROUTE FROM IAH TO CUN. A FIRE BOTTLE WAS DISCHARGED AND THE FLIGHT WAS DIVERTED TO MID. THE FIRE LIGHT EXTINGUISHED ABOUT THREE MINUTES LATER. THE AIRCRAFT LANDED AT MID WITHOUT INCIDENT. MAINTENANCE FOUND NO EVIDENCE OF FIRE OR SMOKE. A LIGHT TEST WAS PERFORMED AND A FIRE WARNING OCCURRED. THE CARGO FIRE ARMING SWITCH WAS REMOVED AND REPLACED DUE TO CONTAMINATION FOUND. OPERATION AND INDICATIONS CHECKED GOOD. BOTH CARGO FIRE BOTTLES WERE REMOVED AND REPLACED IAW MM 26-23-02.