Circuit Description

The vapor pressure sensor and the VSV for the canister closed valve (CCV) 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 P0442 or P0456 is recorded by the ECM when evaporative emissions leak from the components within the dotted line in Fig 1 below, or when the vapor pressure sensor malfunctions.

Fig 1: Checking Abnormalities In Evaporative Emission Control System

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Fig 2: Graphical Representation Of Abnormality Check In Evaporative Emission Control System

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Fig 3: DTC Detection Condition Trouble Area Table

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HINT:

Typical DTC output of each trouble part.

Fig 4: DTC Output Table

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