As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEPARTED PDX EN ROUTE TO LMT. IN CRUISE ENCOUNTERED LIGHT TO MODERATE RIME ICE. AS ICE BUILT THE PROP BEGAN TO VIBRATE. PILOT ADVISED SEA CNTR THAT HE WAS CHANGING DESTINATION TO EUG. PILOT DID NOT DECLARE AN EMERGENCY AND LANDED WITHOUT INCIDENT. TROUBLESHOT PROP DEICE SYSTEM AND REMOVED AND REPLACED 3 PROP BOOT HARNESSES AND 1 DEICE BRUSH BLOCK. AIRCRAFT RETURNED TO SERVICE.