As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FWD LAV SMOKE DETECTOR WENT OFF, ACCOMPANIED BY MASTER WARN. NO ONE IN LAV, NO SMOKE PRESENT. ALARM ACTIVE LESS THAN 10 SEC. REMOVED FROM SERVICE. PERFPRMED GVI OF LAV NO DEFECTS NOTED. C/W LAV SMOKE DETEC SYS CHECK IAW E175 AMM 26-14-01-700-801-A ALL CHECKS GOOD. RETURNED TO SERVICE.