As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED A LAVATORY SMOKE WARNING ECAM MESSAGE ALERTED FOR APPROXIMATELY TEN SECONDS, THE LAVATORYIES WERE REPORTEDLY UNOCCUPIED AND CLEAR AT THE TIME. ACCOMPLISHED OPERATIONAL TEST OF THE SMOKE DETECTION SYSTEM IAW AMM 26-17-00-710-001-A. NO FAULT NOTED.