As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TURNING ON THE PROP DE-ICE, A PROP DE-ICE CAUTION WAS NOTED. MAINTENANCE FOUND THAT THE PROP DE-ICE TIMER WAS STUCK IN ONE CYCLE AND TWO OF THE PROP DE-ICE BOOTS WERE HEATING ALL OF THE TIME, EVEN WITH THE PROP DE-ICE OFF. A REPAIRED DE-ICE TIMER WAS INSTALLED.