As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, THE CREW RECEIVED A RED WARNING PANEL INDICATION FOR A NR 2 BATTERY OVERHEAT. MAINTENANCE CONTROL REQUESTED THAT FLIGHT 4169 TO RETURN TO PIT WHERE MAINTENANCE REPLACED THE NUMBER 2 MAIN BATTERY IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 24-00-00. OPERATIONAL CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.