As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - NR 1 BLEED HOT MASTER CAUTION ILLUMINATED ON DESCENT DUCT TEMPS WERE NORMAL. TURNED BLEEDS OFF PER CHECKLIST LIGHT WENT OUT AFTER A COUPLE MINUTES. MAINTENANCE GROUND RAN BOTH ENGINES, TURNED BLEED AIR ON INDIVIDUALLY AND TOGETHER OPERATED BLEEDS AT MIN AND MAX FLOW. NO FAULTS FOUND. ALL INDICATIONS NORMAL. CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE. NO PARTS REPLACED.