The contact owns a 2013 Ford Focus. The contact stated while driving 73 mph, the contact heard a loud knocking sound and received an electrical shock from the steering wheel. The contact sustained a numb left arm due to the electrical shock but medical attention was not sought. There was no warning light illuminated. The vehicle was not taken to a dealer nor independent mechanic to be diagnosed. The vehicle was not repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 142,938.