What was found
IAH - FLIGHT 3170, DURING PRE-FLIGHT INSPECTION, THE CREW REPORTED THE EMERGENCY EXIT LIGHT ABOVE ROW 12 TO BE INOPERATIVE. MAINTENANCE INSPECTED THE AIRCRAFT, REMOVED AND REPLACED THE AFFECTED EMERGENCY LIGHT BATTERY POWER SUPPLY, OPERATIONALLY CHECKED WITH NO DEFECTS. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.