As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CATERING REPORTED SMOKE TO F/A WENT BACK AND SMELLED SMOKE ABOUT 4 ROWS PRIOR TO THE AFT BULKHEAD. OTHER CREW MEMBERS ALSO NOTICED THE ODOR. FIRST F/A ALSO REPORTED SEEING SMOKE IN THE AFT PART OF THE AIRCRAFT. ISOLATED MAIN ODOR TO APU BATTERY OVERHEATING. REPLACED APU BATTERY AND APU BATTERY CHARGER PER MM.