As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED AN APU OIL TEMP CAUTION MESSAGE IN FLIGHT. CREW PERFORMED AN UNSCHEDULED LANDING IN CMH WITHOUT INCIDENT. MAINTENANCE INSPECTED AND SERVICED THE APU OIL LEVEL. OPERATIONAL CHECKS WERE PERFORMED AND NO DEFECTS NOTED. AIRCRAFT WAS RELEASED FOR SERVICE.