There are 2 owner-reported driver assist & adas complaints for the 2018 Mercedes-Benz S-Classin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Driving on interstate 95 in South Carolina in the high speed lane Saturday December 2 2023 late morning. Adaptive cruise control, lane keep assist, self driving modes engaged. No traffic in front, large semi truck next to passenger side about equal to side mirror, I believe it was advancing. Car sounds collision warning beep and executes full emergency barking with seat belt tensioners emergency retraction. The system quickly releases the brakes which may have been the result of me pressing the gas pedal, I am not sure as this all happened in fractions of seconds. I disengaged all self driving and distronic systems including parking sensors and continued on the journey.
TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ S450. WHILE DRIVING 75 MPH WITH THE CRUISE CONTROL ENGAGED, THE AUTOMATIC BRAKING ACTIVATED ON ITS OWN IN TRAFFIC. THE CONTACT HAD TO DEPRESS THE BRAKE PEDAL TO DISENGAGE THE CRUISE CONTROL IN ORDER TO DRIVE SAFELY. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF ALEXANDRIA (200 S PICKETT ST, ALEXANDRIA, VA 22304, (703) 341-2100) TO BE DIAGNOSED, BUT THE FAILURE COULD NOT BE DUPLICATED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 49,826.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026