ENGINE - 2AZ-FXE ENGINE
02HEG46Y
02HEG47Y
THS
ECU
Purge VSV
(Close)
Atmospheric
Fuel Tank
Pressure Sensor
Fuel Vapor-containment
Valve (Open)
Canister
Leak Detection
Pump (ON)
Canister Pressure Sensor
Canister Pump
Module
Vent Valve (Close)
Leak Detection Pump (ON)
Purge VSV (Close)
Fuel Vapor-containment
Valve (Open)
Fuel Tank Pressure Sensor
Atmospheric Pressure (0 kPa)
Canister Pressure Sensor
at Leak Detection Pump
0.02 in. Pressure
Fuel Tank Leak Check
P1422
P1423
P2451
Vent Valve
(Close)
EG-73
f. Fuel Vapor-Containment Valve Stuck Closed Judgment and Fuel Tank Leak Check
i) Fuel Tank Internal Pressure Equals Atmospheric Pressure
1) The THS ECU actuates the leak detection pump, and turns ON the canister pump module and the
fuel vapor-containment valve (open), in order to introduce a vacuum into the fuel tank, pipe, and
canister.
2) When the pressure in the system stabilizes, the THS ECU compares this pressure with the 0.02 in.
pressure in order to check for a leakage.
3) If the detection value is below the 0.02 in. pressure, the THS ECU determines that there is no
leakage.
4) If the detection value is above the 0.02 in. leak pressure and near atmospheric pressure, the THS
ECU determines that there is a gross leakage (large hole) and stores DTC P1423 in its memory.
5) If the detection value is above the 0.02 in. leak pressure and below near atmospheric pressure, the
THS ECU determines that there is a small leakage and stores DTC P1422 in its memory.
6) At this time, if there is no fluctuation in the fuel tank pressure sensor value, the THS ECU
determines that the fuel vapor-containment valve is stuck closed and stores DTC P2451 in its
memory.