As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT NR 2203, NR 1 WOULD NOT AUTOFEATHER DURING AUTOFEATHER TEST. MAINTENANCE COMPLIED WITH AUTOFEATHER SYSTEM AND POWER UPTRIM TEST NUMEROUS TIMES. OPERATION CHECK GOOD EACH TIME. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.