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: Evaporative Emission Control System Diagram

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Fig 2: Evaporative Emission Control System Mode

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Fig 3: DTC Table

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NOTE:

Typical DTC output of each trouble part.

Fig 4: DTC Output Of Trouble Part Table

*1: ECM may output some other DTCs combination

*2: Refer to DTC P0441 and P0446 DTC P0441 EVAPORATIVE EMISSION CONTROL SYSTEM INCORRECT PURGE FLOW, DTC P0446 EVAPORATIVE EMISSION CONTROL SYSTEM VENT CONTROL CIRCUIT