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 EMERGENCY LIGHTS IN THE REAR OF THE AIRCRAFT WERE FOUND TO BE INOPERATIVE. MAINTENANCE REMOVED AND REPLACED THE NUMBER FOUR EMERGENCY LIGHT BATTERY PACK, OPERATIONALLY TESTED WITH NO DEFECTS, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.