Evaporative Emissions System: Description and Operation

The vapor pressure sensor and VSV for vapor pressure sensor are used to detect abnormalities in the evaporative emission control system.
The ECM decides whether there is an abnormality in the evaporative emission control system based on the vapor pressure sensor signal.
DTC P0440 is recorded by the ECM when evaporative emissions leak from the components within the dotted line in fig. 1 above or when the vapor pressure sensor malfunctions.
DTCs P0441 and P0446 are recorded by the ECM when evaporative emissions leak from the components within the dotted line in fig. 1 below or when there is a malfunction in either the VSV for EVAP, the VSV for vapor pressure sensor or in the vapor pressure sensor itself.
DTC P0450 is recorded by the ECM when the vapor pressure sensor malfunction.