As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT AFTER LEVELING OFF, RECEIVED AUTO PILOT FAIL, AUTO TRIM FAIL MESSAGES AND THE PITCH TRIM INDICATION DASHED OUT. WHEN THE REVERSIONARY BUTTONS DID NOT RETURN THE INDICATION, IT WAS DECIDED TO RETURN TO KCMH WHERE THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED THE HORIZONTAL STAB CONTROL UNIT WITH NO FURTHER DEFECTS NOTED.