What was found
IAH- DURING A WEEKLY CHECK IT WAS NOTED THAT THE AISLE PATH LIGHTING FOR POWER SUPPLY 18WL FAILED TO ILLUMINATE. IAH- MAINTENANCE REMOVED AND REPLACED THE FUSE AT LOCATION 18WL, PERFORMED A OPERATIONAL CHECK OF THE EMERGENCY LIGHTING, NO DEFECTS NOTED, AND, THE AIRCRAFT WAS APPROVED FOIR RETURN TO SERVICE.