Detection of leaks in a device for evaporating vapors of a fuel stored in a vehicle heat engine tank

A device for evaporating vapors of a fuel stored in a motor vehicle tank of a motor vehicle including an engine, the motor vehicle tank being configured to store the fuel configured to burn in said engine, said evaporation device comprising:

• an absorbent filter configured to filter the vapors generated by the fuel stored in said tank;
• a absorption circuit connecting the absorbent filter to the tank to allow the vapors to be conveyed to the absorbent filter;
• a ventilation circuit connecting the outside of the motor vehicle to the absorbent filter, the ventilation circuit comprising an outlet valve configured to switch between an open position in which the outlet valve allows gases filtered by the absorbent filter to escape to the outside, and a closed position in which the evaporation device is isolated from the outside of the motor vehicle;
• a purge circuit connecting the absorbent filter to the engine of the motor vehicle, the purge circuit comprising
• an electric pump configured to allow the vapors absorbed by the absorbent filter to flow to the engine,
• a purge valve configured to switch between an open position, in which said purge valve allows the gases to flow from the absorbent filter to the engine, and a closed position in which the absorbent filter is isolated from the engine, and
• a pressure measurement sensor mounted between a connection point with the electric pump, and the purge valve;
• a bypass circuit;
• and
• a bypass valve mounted between the absorption circuit, the purge circuit, and the tank, the bypass valve being connected to the purge circuit by the bypass circuit at the connection point, the bypass valve being configured to move between an absorption position, in which the bypass valve allows the gases to flow between the tank and the absorbent filter via the absorption circuit, and a leak detection position, in which the bypass valve allows the gases to flow between the purge circuit and the tank via the bypass circuit,
• wherein the electric pump is configured to draw in gases from the outside to convey the outside gases, via the ventilation circuit, the absorbent filter, and the bypass circuit, to the tank, in order to pressurize said tank and allow the detection of a leak in the evaporation device by the pressure measurement sensor.