As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER LEVELING OFF AT FL350, THE CREW RECEIVED A LAVATORY SMOKE WARNING MESSAGE. AFTER 10 SECONDS, THE MESSAGES EXTINGUISHED. HAD THE F/A CHECK THE LAVATORIES FOR FIRE OR SMOKE. NO FAULTS NOTED. MX INSPECTED THE SMOKE DETECTOR SYSTEM. NO FAULTS FOUND. PERFORMED OPS CHECK OF THE SYSTEM IAW AMM. NO DEFECTS NOTED. OPS CHECKED GOOD.