As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TLH/TPA - FLT 3421 - DURING FLIGHT, THE SMOKE WARNING LIGHT AND MASTER WARNING LIGHT CAME ON IN-FLIGHT. LIGHT WENT OUT AFTER 10 MINUTES, CAME BACK ON, AND WENT OUT AFTER LANDING. REMOVED AND CLEANED CANNON PLUGS ON BOTH DETECTORS AFT OF CARGO COMPARTMENT. (X)