Wiper Signal 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.
When the driving support ECU assembly detects that the wipers are operating at high speed, control of vehicle speed by the dynamic radar cruise control system is canceled.