NHTSA complaint #11423701

Owner complaint summary

On 6/8/2021, when pulling out of my driveway approximately 9:00 am, I experienced the car switching from Hybrid mode to Sport mode without me engaging the Sport mode control. The following day (6/9/2021), after a day of primarily interstate driving (over 200 miles), while stopping at a red light, I felt the brake pedal fall to the floor faster than I was applying pressure and I came to a sudden stop. The brakes had seized and the car was towed to Thompson BMW. The tow driver was able to release the brakes by pulling up the brake pedal. Thompson BMW could not recreate the brake failure but their diagnostics indicated brake failure. BMW NA was called as my car was less than 6 months old with 9724 miles. The service advisor told me that they were instructed to replace the Master Cylinder but could not tell me why brakes failed. Knowing that this was a significant safety concern, I opened a safety complaint with BMW. BMW could not tell me the root cause of the brake failure and as a result, I had no confidence that the problem was “fixed”. Master cylinders rarely fail. They also refused to provide me the diagnostics report. They said I was only entitled to the maintenance invoice. Linda Vitale was assigned my complaint and in a voicemail, told me I lost power to the DSCI module. She said the DSCI “has a fail-safe mode and if no power was present the conventional brakes” would work. They replaced the DSCI module and “it should be fine.” Based on her email, and then conversation, BMW engineering said I had an electrical issue. So why did the conventional brakes fail? I am very concerned that BMW has not identified the real problem and I can experience this brake failure again. If this failure had occurred while braking on an interstate highway, I could have been killed or vehicle could have caused fatal accident. I am extremely concerned about the safety of this vehicle, especially since over 60% of my driving in on highways and interstates.