As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE TO CLT, THE CREW RECEIVED A MAIN BATTERY OVERHEAT CAS MESSAGE. FLIGHT 4044 RETURNED TO CAK FOR MAINTENANCE. MAINTENANCE INSPECTED AND REPLACED A TEMPERATURE SENSOR IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 24-00-00. OPERATIONAL CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.