As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 2757 - EWR - FLIGHT CREW REPORTED LAV SMK INDICATION SHORTLY AFTER TAKEOFF, NO SMOKE OR FIRE DETECTED BY THE FLIGHT ATTENDANT. SMOKE DETECTOR IN GALLEY BLINKING GREEN TO RED. EWR MX REMOVED AND REPLACED LAV SMOKE DETECTOR AND PERFORMED OPERATIONAL CHECK SUCCESSFULLY. AIRCRAFT WAS APPROVED TO RETURN TO SERVICE.