As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT 3225 ON TAKEOFF THE CREW REPORTED A LAVATORY SMOKE DETECTION MESSAGE AND SMOKE ODOR IN THE AFT CABIN. THE CREW ELECTED TO RETURN TO CID. THE AIRCRAFT LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE RIGHT ENGINE IAW WC 11-00-00. REMOVED AND REPLACED THE NR 4 CARBON SEAL. OPERATIONAL LEAK CHECK GOOD. NO SMOKE SMELL FROM PACKS WAS DETECTED. THE AIRCRAFT WAS RETURNED TO SERVICE.