As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UNEXPLAINED AFT RIGHT-HAND LAVATORY SMOKE DETECTOR WARNING. *S/D* NO SIGNS OF SMOKE AND/OR FIRE DAMAGE WERE IDENTIFIED IN THE LAVATORY, AND NO SIGNS OF TAMPERING AND/OR DAMAGE TO DETECTOR WERE NOTED. OPERATIONAL CHECK TESTED OK. THERE HAVE BEEN NO SUBSEQUENT REPORT OF THIS DETECTOR ERRONEOUSLY GOING OFF.