Nissan has begun testing its Leaf-based autonomous car prototype, not on private property, but on Japanese inner city roads and highways. To be exact, the automaker wants to put its "Piloted Drive" mode (part of its Intelligent Driving System) to the test, which can take control of the car in certain conditions. The mode's first version, which Nissan wants to add to production models by the end of 2016, enables a car to drive autonomously in heavy traffic on the highway. The company hopes to roll out the ability to change lanes by 2018, as well as the power to navigate city roads and intersections without human input by 2020.