What was found
IAH-DURING PREFLIGHT THE CREW NOTED THAT THE ROW 9 OVERHEAD EMERGENCY LIGHTS FAILED TO ILLUMINATE ABOVE SEATS 9A, AND, 9B. IAH- MAINTENANCE REMOVED AND REPLACED THE LIGHT BULBS IN THE EXIT LIGHT, PERFORMED A OPERATIONAL CHECK OF THE EMERGENCY LIGHTING SYSTEM, NO DEFECTS NOTED, AND, THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.