As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 1228, FLL-CLT: DURING FLIGHT, CREW REPORTED AN OVERHEAT ODOR AND THE 2L LAV SMOKE DETECTOR SOUNDING. FLIGHT LANDED IN CLT WITH NO DIFFICULTIES. MAINTENANCE PLACED THE LEFT PACK ON MEL 21-5101 AND REPLACED THE 2L LAV SMOKE DETECTOR. SUBSEQUENT TROUBLESHOOTING FOUND THAT THE APU HAD AN INTERNAL OIL LEAK, CAUSING CONTAMINATION OF THE AIR DISTRIBUTION SYSTEM. REPLACED APU. NO FURTHER FAULTS.