What separates Active Driving Assist from plain old adaptive cruise control is a more sophisticated sensor suite that involves cameras that inform the various other ADAS systems, as well as three forward-looking and two-rear-facing radar units. The system also uses a predictive algorithm to infer the intended direction of travel and to keep the vehicle centered in the lane. But in 2021 Jeep Grand Cherokee L models equipped with the feature, you'll have to keep a hand on the wheel.