ECU Power Source Circuit [12/2013 - 11/2016]: Description
WARNING: This page is about a different car, the 2016 Toyota Highlander, 2015 Toyota Highlander, and 2014 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
This circuit provides power to operate the driving support ECU assembly. The driving support ECU assembly determines information about the vehicle in front based on data from the radar sensor, and then decides how much acceleration and/or deceleration is needed to maintain the set vehicle-to-vehicle distance. The driving support ECU assembly also requests to apply braking.