As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED. LAVATORY SMOKE DETECTOR LIGHT ILLUMINATED FOR 5 SECONDS THEN OFF. FLIGHT ATTENDANT REPORTED SMOKE ALARM IN FIRST CLASS LAVATORY BRIEFLY. NO EVIDENCE OF SMOKE OR ODOR IN ANY LAVATORY. PERFORMED LAVATORY SMOKE DETECTION TEST PER AMM 26-14-00. OPERATIONAL CHECK GOOD.