As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE WAS REPORTED IN THE CABIN SHORTLY AFTER TAKEOFF. SMOKE CLEARED PRIOR TO LANDING A FEW MINUTES LATER. AFT LAV SMOKE DETECTOR SOUNDED. FLIGHT LANDED BACK AT RAP SAFELY. MAINTENANCE RAN PACKS AND APU, CHECKED FOR WIRING FAULTS OR HOT BALLAST. NO TROUBLE FOUND IN ANY COMPONENTS. TWO DAYS LATER APU DISCOVERED LEAKING OIL AND LEAKS CORRECTED. AIRCRAFT RETURNED TO SERVICE.