As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE ENCODER FOR CABIN PRESSURIZATION SYSTEM LOCATED FORWARD OF THE INSTRUMENT PANEL AND ABOVE THE PEDESTAL, SEPARATED FROM THE MOUNTING BRACKET AND LODGED IN THE ELEVATOR CONTROL QUADRANT, RESULTING IN LIMITED ELEVATOR CONTROL FOR THE PILOT ON APPROACH TO LANDING. THE THUMB NUT SECURING THE ENCODER TO ITS MOUNTING BRACKET LOOSENED OR WAS NOT INSTALLED PROPERLY AND ALLOWED THE ENCODER TO FALL INTO THE ELEVATOR CONTROL SYSTEM. NEEDS A WAY TO SAFETY THE HARDWARE HOLDING THE ENCODER IN PLACE.