As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON LANDING ROLL OUT, UNCOMMANDED ELEVATOR TRIM ACTUATION TO 9.8 UNITS NOSE UP. INTERROGATED MDC NO FAULTS FOUND. FUNCTION TEST OF HSTCU GOOD, NO EVIDENCE OF MOISTURE INGRESS. REMOVED AND REPLACED HSTCU, FUNCTION CHECK GOOD. FDR TO BE DOWNLOADED IN ORF. CAPTAINS AND F/O`S TRIM SWITCHED GOOD, NO DEFECTS. (M)