As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT 2321: ON FINAL, WITH POWER AROUND 20 PERCENT, DEICE PRESSURE CAUTION LIGHT CAME ON. DEICE PRESSURE INDICATED NORMAL. AS PER CHECKLIST, TURNED OFF THEN BACK ON. DEICE PRESSURE LIGHT CAME BACK ON. DEICE PRESSURE GAUGE SHOWED NORMAL. MAINTENANCE PERFORMED A GVI FROM GOUND LEVEL, LOOKED GOOD. C/W FUNCTIONAL TEST OF AIRFRAME DEICE SYSTEM IAW Q400 TR 30-047, TASK 30-11-00-720-801. OPS CHECK GOOD. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.