The contact owns a 2013 Toyota Prius V. The contact stated that while driving at an undisclosed speed, there was an abnormal sound coming from the engine compartment. The service brakes and traction control warning lights were illuminated. The vehicle was taken to an independent mechanic, who diagnosed failures with the brake booster and master cylinder assembly, resulting in an abnormal leak in the brake accumulator pressure. The vehicle was not repaired. After investigating the failure, the contact related the failure to the Customer Satisfaction Program: 20TE07. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 63,000.