As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 4938 - JFK - SMOKE WARNING INBOUND TO JFK. THE CREW DISCHARGED 1 EXTINGUISHER BOTTLE. INSPECTION OF THE AFT CARGO COMPARTMENT PROVED IT WAS A FALSE WARNING. CLEANED DETECTOR LENS. ALSO, REMOVED AND REPLACED THE EXTINGUISHER BOTTLE.