As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 4103. CREW REPORTED THAT AFTER TAKEOFF, RECEIVED AN EICAS LAV SMOKE WARNING MESSAGE. DECLARED AN EMERGENCY AND COMPLETED AOM VOL 1 PROCEDURES AND RETURNED TO DEPARTURE. MESSAGE EXTINGUISHED ON APPROACH. LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REMOVED AND REPLACED THE LEFT ENGINE CARBON SEAL ASSEMBLY IAW MM 72-25-25, NO SMOKE WARNINGS, BURNING ODORS OR OIL LEAKAGE NOTED AT THIS TIME. AIRCRAFT RETURNED TO SERVICE.