P0440

P0440 - Evaporative Emission Control System Malfunction

CIRCUIT DESCRIPTION

DTC Detecting Condition:

The vapor pressure sensor, VSV for Canister Closed Valve (CCV) and VSV for pressure switching valve are used to detect abnormalities in the evaporative emission control system.
The ECM decides whether or not there is an abnormality in the evaporative emission control system by the vapor pressure sensor signal.
DTC P0440 is recorded by the ECM when evaporative emissions leak from the components within the dotted line, or when the vapor pressure sensor malfunctions.

Wiring Diagram:

Step 1 - 6:

Step 7 - 10:

Step 11 - 12:

INSPECTION PROCEDURE

HINT:
- If DTC P0441, P0446, P0450 or P0451 is output after DTC P0440, first troubleshoot DTC P0441, P0446, P0450 or P0451. If no other malfunctions than them are detected, troubleshoot DTC P0440 next.
- Ask the customer whether or not, after the MIL came on, the customer found the fuel tank cap was loose and tightened it. Also ask the customer whether the fuel tank cap was loose when refuelling. If the fuel tank cap was loose, the DTC is suspected. If the fuel tank cap was not loose or if the customer was not sure if it was loose, troubleshoot according to the following procedure.
- Read freeze frame data using the TOYOTA hand-held tester or OBDII scan tool, as freeze frame data records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.