As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF SMOKE ALARMS IN 3 LAVS SOUNDED AND FUMES WERE PRESENT IN THE CABIN. AIRCRAFT RETURNED TO DEPARTURE AIRPORT. MAINTENANCE RAN ENGINES AT TAKEOFF POWER WITH PACKS ON TO BURN OUT RESIDUAL OIL FROM A PREVIOUS APU OIL LEAK. ACM AND WATER SEPARATORS WERE REPLACED.