As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - DURING MAINTENANCE INSPECTION, THE BATTERY IN EMERGENCY POWER SUPPLY 3WL WAS FOUND TO BE INOPERATIVE. MAINTENANCE REMOVED AND REPLACED THE AFFECTED BATTERY AND OPERATIONAL CHECKED GOOD IAW ATR 42-320 JIC 33-51-21, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE. (M)