As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 2943 - EWR - FLIGHT CREW REPORTED LAV SMOKE IND ON EICAS. CREW PERFORMED AIR RETURN AND LANDED AIRCRAFT UNEVENTFULLY. EWR MX REMOVED AND REPLACED LAV SMOKE DETECTOR AND PERFORMED OPERATIONAL CHECK SUCCESSFULLY. AIRCRAFT WAS APPROVED TO RETURN TO SERVICE.