DTC P2450: Fuel Vapor-containment Valve Stuck Open; DTC P2451: Fuel Vapor-containment Valve Stuck Closed [02/2014 - 11/2015]: 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.
The description can be found in EVAP (Evaporative Emission) System.
Refer to DESCRIPTION