One problem related to blind spot detection has been reported for the 2019 Audi S4. The most recently reported issues are listed below.
The contact owns a 2019 Audi S4. The contact stated that while driving approximately 60 mph, the brakes locked up. The abs warning light was illuminated. The Audi pre-sense message was also displayed. The vehicle was taken to fletcher jones Audi (1523 w. North Ave, chicago, IL 60642, (312) 628-4300) however, the mechanic was unable to determine the cause of the failure. The vehicle was not diagnosed nor repaired. The manufacturer was notified of the failure. The failure mileage was approximately 19,800.