As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED LAVATORY SMOKE MESSAGE ON EICAS TWICE DURING CRUISE, NO SMOKE NOTED. MX R & R THE SMOKE DETECTOR SENSOR WITH OPS CHECKED SUCCESSFUL AND PERFORMED ENGINE RUNS AT HIGH POWER WITH NO SMOKE NOTED. ACFT WAS APPROVED FOR RETURN TO SERVICE.