As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN AUTOPILOT ON, GRINDING NOISE FROM UNDER COCKPIT FLOOR. DEFERRED ELEVATOR TRIM SYSTEM. CLEANED DEBRIS FROM TRIM WHEEL STOP TRACKS AND INSPECTED SERVOS BENEATH FLOORBOARDS. NO DEFECTS NOTED. TRIM SYSTEM OPERATIONAL CHECKS GOOD IAW MM 22-10-00.