Summary: The Office of Defects Investigation (ODI) has identified 508 complaints alleging loss of power steering assist and increased steering effort in model year (MY) 2010 to 2012 Ford Fusion, Mercury Milan and Lincoln MKZ vehicles equipped with rack mounted Electric Power Assisted Steering (EPAS). Four of these complaints allege that the steering assist failure resulted in increased steering efforts that contributed to a loss of control and crash. In addition, ODI has identified related information in Early Warning Reporting field report data submitted by Ford. Many of the complaints indicated observing a power steering warning message as the failure occurred. In some cases, the condition was corrected by turning the vehicle off and restarting. However, many reports indicate the condition returned again after restart. A Preliminary Evaluation has been opened to assess the scope, frequency and safety consequences of the alleged defect.