As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF CLIMBING THRU 4,000 FT, AFT SMOKE MASTER WARNING OCCURRED AND REMAINED FOR ABOUT 15 SECONDS. AIRCRAFT DIVERTED BACK TO MIA. NO SMOKE OR FIRE INDICATION WAS VISIBLY BY CREW OR CRASH FIRE AND RESCUE CREW. REMOVED AND REPLACED AFT CARGO SMOKE DETECTOR AS PER JIC NR 26-15-21. PERFORMED OPERATIONAL CHECK AND FOUND WORKING PROPERLY AS PER JIC NR 26-15-00.