As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - DURING 'A' CHECK INSPECTION, THE EMERGENCY BATTERY AT LOCATION 3WL FAILED TO ILLUMINATE ITS ASSOCIATED EMERGENCY LIGHTS. MAINTENANCE REMOVED AND REPLACED THE BATTERY PACK IAW ATR42-320 JIC 33-51-21, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE. (M)