Inspection Using Generic OBDII Scan Tool

DTC P0446 Evaporative Emission Control System Vent Control Malfunction

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CIRCUIT DESCRIPTION
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 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.





DETECTING CONDITION





WIRING DIAGRAM

INSPECTION PROCEDURE

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TOYOTA hand-held tester

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OBDII scan tool (excluding TOYOTA hand-held tester)

HINT: If DTC P0441, P0446 or P0450 is output after DTC P0440, first troubleshoot DTC P0441, P0446 or P0450. If no malfunction is detected, troubleshoot DTC P0440 next.

For additional information regarding DTC codes P0441 and P0446 see TSB EG003-98