As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ELEVATOR TRIM SCREW JACK ASSEMBLY SPROCKET SPINS WITHOUT ANY MOVEMENT OF SCREWDRIVE. FOUND KEY, P/N NAS558P404-8 TO BE MISSING CAUSING NO ELEVATOR TRIM TO BE AVAILABLE ON RIGHT SIDE. REFERENCE DASH 8/300 IPC 27-38-00; FIGURE 15; ITEM 160. SCREW JACK REPLACED.