Circuit Description
WARNING: This page is about a different car, the 2003 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
The vapor pressure sensor, the VSV for the canister closed valve (CCV) and the VSV for the pressure switching valve are used to detect abnormalities in the evaporative emission control system. See Fig 1. The ECM decides whether there is an abnormality in the evaporative emission control system based on the vapor pressure sensor signal. DTCs P0441 and P0446 are recorded by the ECM when evaporative emissions leak from system components, or when there is a malfunction in either the VSV for the EVAP, the VSV for the pressure switching valve, or in the vapor pressure sensor itself.