The contact owns a 2015 Audi SQ5. The contact stated while driving at approximately 65 MPH, while the brake pedal was depressed, the brakes failed to engage; the contact had to initiate the emergency brake to bring the vehicle to a halt. No warning light was illuminated. The vehicle was towed to an independent mechanic to get a diagnosis however, the diagnosis was pending. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 108,084.