As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOTH CAPTAIN & FLIGHT OFFICER'S MASTER WARNING CAME ON WITH AURAL WARNING MSG. APPEARED TO BE LAVATORY SMOKE DETECTOR. WARNING WAS SHORT LIVED & COULDN`T RECALL OR SHOW IN STS. POST FLIGHT REPORT SHOWED ECAM WARNING SMOKE LAVATORY SMOKE, NO ACTIVE MSGS OR FAULTS. BITE CHECK OF SDCU & FLIGHT ATTENDANT PANEL LAVATORY SMOKE SYS HAD NO FAULTS. RESET CIDS IAW AMM 26-17-00-710-001, RESET NORMAL.