As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CRUISE FLIGHT AT 16000 MSL, RIGHT PROP PITCH ANNUNCIATOR ILLUMINATED. NO OTHER INDICATIONS ON INSTRUMENTS. NO AFFECTS ON AIRCRAFT HANDLING WERE DETECTED IN FLIGHT. CREW ELECTED TO RETURN TO HOME BASE. IN ANTICIPATION OF POSSIBLE ASYMMETRIC THRUST ON LANDING, DECLARED EMERGENCY SO THAT EMERGENCY EQUIPMENT WOULD BE STANDING BY. LANDING WAS UNEVENTFUL. MAINTENANCE REMOVED AND REPLACED DEFECTIVE RIGHT PROP PROXIMITY SWITCH.