As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - SMOKE WARNING ILLUMINATES IN FLIGHT FOR ONE MINUTE THEN WENT OUT. MAINTENANCE MET AIRCRAFT ON ARRIVAL. NO SMOKE OR ODOR DETECTED. INSPECTED BOTH SMOKE DETECTORS AND RESEATED CANNON PLUGS, REPLACED. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE. NO PARTS REPLACED.