As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT LEFT LAVATORY SMOKE DETECTOR ALARM SOUNDED TWICE. STOPPED BY ITSELF. THE FLIGHT DECK LAVAVATORY SMOKE LIGHT AND BELL SOUNDED ONCE THEN STOPPED. REMOVED AND REPLACED SDCU IAW MM. REPLACED AFT LEFT LAVATORY SMOKE DETECTOR. OPS CHECKED GOOD.