As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT NR 2486: THE CAPTAIN'S SIDE PROP DEICE WAS CAUSING THE PROP DEICE CAUTION LIGHT TO ILLUMINATE. AIRCRAFT RETURNED TO FIELD. MAINTENANCE REMOVED AND REPLACED NR 6 PROP DEICE WIRE HARNESS IAW Q400 AMM 61-10-06-400-805. PERFORMED FUNCTIONAL TEST OF PROP DEICE SYSTEM IAW Q400 AMM 30-61-00-720-801. OPS CHECK GOOD WITH NO FURTHER DEFECTS NOTED. AIRCRAFT RETURNED TO SERVICE.