As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) APS-65 AUTOPILOT INSTALLED IN DHC6-300 BY MANUFACTURERS SERVICE BULLETIN SB 6-505 IS NOT MENTIONED IN THE AIRCRAFT MAINTENANCE MANUAL, HAS NO INSTRUCTIONS FOR CONTINUED AIRWORTHINESS OR INSPECTION REQUIREMENTS. THERE IS NO PROCEDURE FOR TESTING SYSTEM POST MAINTENANCE OTHER THAN PRE-FLIGHT GROUND TEST. (TC# 20190410021)