Multi-compartment liquid reservoir for a motor vehicle

Multi-compartment liquid reservoir (10) for a motor vehicle, comprising a first fluid compartment (14) equipped with a fluid inlet (18) and with a fluid outlet (22), and a second fluid compartment (16) equipped with a fluid inlet (20) and with a fluid outlet (24), the reservoir comprising a liquid-filling neck (12) and the first fluid compartment and the second fluid compartment being in fluid communication via at least one passage (30) allowing one of the first fluid compartment or the second fluid compartment to be filled via the other of the first fluid compartment or the second fluid compartment, the reservoir further comprising at least one shut-off system (44), able to move between a first position of opening of the at least one passage and a second position of closure of the at least one passage, wherein the shut-off system is configured to adopt the first position by default and in a free state, and to be urged into the second position, when the reservoir is in operation, when a fluid is circulating from the inlet to the outlet of one of the first fluid compartment or the second fluid compartment, wherein the first fluid compartment and the second fluid compartment (14, 16) communicate with one another by at least one venting and expansion tube (38), a lower end of which is connected to the first fluid compartment and an upper end of which is situated in the second fluid compartment and above a maximum level for liquid in the first fluid compartment (14).