As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT NR 2350: AFTER PUSHBACK, NOTICED PROP DE-ICE CAUTION LIGHT WAS ILLUMINATED. FOLLOWED PROP DE-ICE CAUTION CHECKLIST. LIGHT REMAINED ILLUMINATED. MAINTENANCE FOUND NO FAULTS IN CDS. CLEARED NVM ON NR 1 AND NR 2 PROP DE-ICE. CAUTION LIGHT EXTINGUISHED. TESTED NR 1 AND NR 2 PROP DE-ICE IAW DHC-400 MM 30-61-00-720-801 NUMEROUS TIMES. NO FURTHER FAULTS NOTED. OPS CHECK ALWAYS GOOD DURING TESTING. AIRCRAFT RETURNED TO SERVICE.