What was found
IAH FLIGHT 2196, THE CREW REPORTED A WINDSHIELD 2 HEAT FAIL MESSAGE FOLLOWED BY A SMOKE SMELL IN THE COCKPIT. THE CREW DEACTIVATED THE F/O'S WINDSHIELD HEAT, AND THE AIRCRAFT RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE F/O'S WINDSHIELD HEAT CONTROLLER, OPERATIONALLY CHECKED WITH NO DEFECTS, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.