F Repeat in Leak Pressure Measurement

1) While the ECM operates the vacuum pump, the purge VSV and vent valve turn off and a repeat 0.02 in. leak pressure measurement is performed.

2) The ECM compares the measured pressure with the pressure during EVAP leak check.

3) If the pressure during the EVAP leak check is below the measured value, the ECM determines that there is no leakage.

4) If the pressure during the EVAP leak check is above the measured value, the ECM determines that there is a small leakage and stores DTC P0456 in its memory.

01meg03y

Purge VSV ON (Open) Purge VSV OFF (Close)

Vent Valve

Pump Motor

OFF (Vent) ON OFF

Atmospheric Pressure

System Pressure

0.02 in. Leak Pressure

Purge VSV ON (Open) Purge VSV OFF (Close)

OFF (Vent) ON OFF

Atmospheric Pressure

System Pressure

0.02 in. Leak Pressure

275tu51

Repeat 0.02 in. Leak Pressure Measurement

Repeat 0.02 in. Leak Pressure Measurement

275tu51

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