NHTSA Complaint #11701566 — 2023 MERCEDES-BENZ EQS 580 4MATIC

The contact owns a 2023 Mercedes-Benz EQS580 4Matic. The contact stated that the vehicle was designed with Level 2 Semi-Autonomous Driving System and was purchased brand new. The contact stated that the first failure had occurred in the first month of purchase. The contact stated that while driving with the Adaptive Cruise Control with the Stop-and-Go Mode engaged, the set speed changed radically. The contact stated that while the speed was set to 60 MPH, the speed decelerated to 20 MPH unintendedly. No warning light was illuminated. The vehicle was taken to the dealer, but the cause of the failure could not be determined. The contact stated that a staff at the dealer advised the contact that it was a known issue with similar vehicles. The contact stated that the failure recurred while the dealer was test-driving the vehicle. The vehicle was not repaired. The contact stated that the failure persisted. The contact stated that upon taking the vehicle back to several dealers on several occasions and the contact was provided a loaner vehicle; however, the same failure occurred with the loaner vehicles. The manufacturer was not notified of the failure. The failure mileage was approximately 200.