Method for controlling a vehicle drive train comprising two cooling circuits

1. A method for controlling a power train of a vehicle, comprising:

placing two cooling circuits that operate in a normal way, a first one of the cooling circuits associated with a combustion engine and a second one of the cooling circuits associated with at least one electric member, in fluidic communication by at least one valve in a first position;

detecting a temperature of fluid circulating in the first one of the cooling circuits;

adjusting, when the temperature in the first one of the cooling circuits rises above a first predetermined threshold, the at least one valve to a second position in which the fluid circulating in the second one of the cooling circuits does not circulate in the first one of the cooling circuits such that the fluid in the second one of the cooling circuits does not cool the combustion engine; and

adjusting, when the temperature of the fluid in the first one of the cooling circuits rises above a second predetermined threshold that is hotter than the first predetermined threshold, the at least one valve to a third position in which the fluid arriving in the second one of the cooling circuits from the first one of the cooling circuits is conveyed through an electronics radiator in the second one of the cooling circuits before returning to the first one of the cooling circuits.

2. The method as claimed in claim 1 , wherein the electric member or one of the electric members comprises an electric motor.

3. The method as claimed in claim 2 , wherein the communication is established or maintained when the vehicle is being propelled by the electric motor alone.

4. The method as claimed in claim 3 , the communication is established or maintained during a cold start.

5. The method as claimed in claim 3 , wherein the communication is established or maintained when cabin heating is required.

6. The method as claimed in claim 3 , wherein the communication is established or maintained when cooling of the combustion engine and/or of a turbocompressor is required.

7. The method as claimed in claim 2 , wherein the communication is established or maintained when the vehicle is being propelled by the combustion engine and the electric member simultaneously.

8. The method as claimed in claim 7 , wherein the communication is established or maintained during a cold start.

9. The method as claimed in claim 2 , wherein the communication is established or maintained when the vehicle is being propelled by the combustion engine alone.

10. The method as claimed in claim 1 , wherein the adjusting the at least one valve to the second position causes an interruption in the communication and is established when the vehicle is being propelled by the combustion engine alone.

11. The method as claimed in claim 10 , wherein the interruption is established or maintained when the fluid in the first one of the cooling circuits is running hot.

12. The method as claimed in claim 1 , wherein the adjusting the at least one valve to the second position causes an interruption in the communication and is established when the vehicle is being propelled by the combustion engine and the electric member simultaneously.

13. A vehicle, comprising:

control means;

two cooling circuits, including a first one of the cooling circuits that is associated with a combustion engine and a second one of the cooling circuits that is associated with at least one electric member; and

at least one valve that places the two cooling circuits in communication with each other when the at least one valve is in a first position,

wherein the control means controls establishment or maintenance of communication between the two cooling circuits that operate in a normal way,

wherein, when a temperature in the first one of the cooling circuits rises above a predetermined threshold, the control means adjusts the at least one valve to a second position in which fluid circulating in the second one of the cooling circuits does not circulate in the first one of the cooling circuits such that the fluid in the second one of the cooling circuits does not cool the combustion engine, and

wherein, when the temperature of the fluid in the first one of the cooling circuits rises above a second predetermined threshold that is hotter than the first predetermined threshold, the control means adjusts the at least one valve to a third position in which the fluid arriving in the second one of the cooling circuits from the first one of the cooling circuits is conveyed through an electronics radiator in the second one of the cooling circuits before returning to the first one of the cooling circuits.

14. The vehicle as claimed in claim 13 , wherein the number of valves is less than or equal to two.

15. The vehicle as claimed in claim 13 , wherein the at least one valve is a three-position valve.