EVAP System Function Test
Vehicles With High Voltage System:
- In electric driving mode the Tank Switch-Off Valve -N288- -4- closes the breather line -6- to the EVAP canister -2-, so that for example on a drive for days it is not overfilled with fuel vapor.
- Because the pressure in the fuel tank -3- increases due to temperature effects when the breather line is closed, the Fuel Tank Pressure Sensor -G400- -5- monitors the tank-internal pressure and via the engine control module causes the Solenoid Valve 1 -N288- to open at a residual pressure of 0.3 bar (4.3 psi). Additionally the valve opens when the fuel filler door release button is pressed, so that no fuel can squirt out of the filler neck when opening the cap to fuel.
1 - EVAP Canister Purge Regulator Valve 1 -N80- to the engine