As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TYS DURING A SCHEDULED INSPECTION, THE EMERGENCY AISLE LIGHTING SYSTEM BATTERY SUPPLY NUMBER 4 WAS FOUND DEAD. MAINTENANCE REMOVED AND REPLACED NR 4 EMERGENCY LIGHT BATTERY, IAW EMB-145-MM-33-50-04. OPERATIONAL CHECKS WERE GOOD. THE REPAIR WAS SATISFACTORY AND THE AIRCRAFT WILL BE RELEASED UPON COMPLETION OF INSPECTION.