on the motor 1 and on the electronic power circuit 2 are connected in parallel with one another by ducts in which the same coolant fluid circulates in the rest of the description for simplification purposes for the elements that are not themselves traveled through by the coolant fluid of the cooling circuit but that are simply thermally connected to the cooling circuit for example by means of heat exchangers this is the case of the motor 1 of the electronic power circuit 2 the presence of such heat exchangers will not be mentioned and mention will be made directly of the element thermally connected to the cooling circuit the motor 1 and the electronic power circuit 2 thermally connected in parallel and the radiator 3 and the electric pump 5 form a hot loop this hot loop makes it possible to transfer the calories transported by the coolant fluid heated in contact with the motor 1 and with the electronic power circuit 2 to the air outside the vehicle the cooling radiator 3 is thermally connected in series with the motor 1 and the electronic power circuit 2 the hot loop and the cooling radiator 3 form the cooling circuit of the vehicle as shown in fig1 a heating radiator 4 is thermally connected in parallel with the motor 1 and the electronic power circuit 2 this heating radiator 4 is placed so as to allow the hot coolant fluid leaving the hot loop to give up the calories that it transports to the air of the passenger compartment of the vehicle by means of the fan 15 in the example shown the cooling radiator 3 is connected to the outlet of the cooling exchanger of the motor 1 and to.