As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA-OUT OF 2000 FEET ON DEPARTURE FROM PDX, LAVATORY SMOKE DETECTOR ACTIVATED. FLIGHT ATTENDANT CHECKED, NO SMOKE/FUMES. PUSHED RESET/TEST, ALARM STOPPED. REMOVED AND REPLACED LAVATORY SMOKE DETECTOR. OPERATIONAL CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.