The contact owns a 2020 Lexus ES 350. The contact stated that while his father was driving at 35-37 MPH down a hill, he applied the brake pedal, but the brakes failed to respond. The contact continued to pump the brake pedal. The driver moved the gear shifter, attempting to slow down the vehicle. The driver crashed into a 2016 Mazda 3, which crashed into a 2017 Honda Civic. There was an unknown brake indicator light displayed. The passenger occupant sustained extreme chest and neck pain. The driver and passenger were provided medical attention. Additionally, the two occupants of the Mazda sustained leg and neck pain but no medical attention was provided. The unknown occupant (s) of the Honda sustained back, feet, neck, and head injuries, and medical attention was provided. The passenger occupant confirmed that the driver had pumped the brake pedal. The vehicle was towed to a lot. The air bags deployed. There was no reported fire. The contact tested the brakes and showed resistance. The contact had an independent mechanic test the vehicle, and the OBD reading showed no results. There was an indication of a low battery. A police report was filed. The police tested the vehicle and noted the brakes were functioning. The contact stated that a witness traveling behind the driver did not see any brake lights illuminate. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximate