Control device for cooling system

A control device for a cooling system, which controls the cooling system in a vehicle including an internal combustion engine, an EGR device including an EGR cooler, and the cooling system that is able to cool cooled objects, including the internal combustion engine and the EGR device, through circulation of coolant,

• the cooling system including
• a flow passage portion that is able to pass the coolant and that includes an engine cooling flow passage for cooling the internal combustion engine, an EGR cooling flow passage for cooling the EGR device, a radiator flow passage that passes through a radiator and a bypass flow passage that bypasses the radiator;
• and
• adjusting means for being able to adjust a circulation amount of the coolant in a first flow passage including the engine cooling flow passage, the EGR cooling flow passage and the radiator flow passage and a second flow passage including the engine cooling flow passage, the EGR cooling flow passage and the bypass flow passage and not including the radiator flow passage, the control device comprising:
• an electronic control unit configured to:
• (i) measure a temperature of the coolant;
• (ii) limit circulation of the coolant at starting the internal combustion engine;
• and
• (iii) circulate the coolant preferentially through the second flow passage via control over the adjusting means based on the measured temperature in a period in which circulation of the coolant is limited,
• (iv) prohibit circulation of the coolant before the coolant is circulated preferentially through the second flow passage.

A control method for a cooling system, which controls the cooling system in a vehicle including an internal combustion engine, an electronic control unit, an EGR device including an EGR cooler, and the cooling system that is able to cool cooled objects, including the internal combustion engine and the EGR device, through circulation of coolant,

• the cooling system including
• a flow passage portion that is able to pass the coolant and that includes an engine cooling flow passage for cooling the internal combustion engine, an EGR cooling flow passage for cooling the EGR device, a radiator flow passage that passes through a radiator and a bypass flow passage that bypasses the radiator;
• and
• adjusting means for being able to adjust a circulation amount of the coolant in a first flow passage including the engine cooling flow passage, the EGR cooling flow passage and the radiator flow passage and a second flow passage including the engine cooling flow passage, the EGR cooling flow passage and the bypass flow passage and not including the radiator flow passage, the control method comprising:
• measuring, by the electronic control unit, temperature of the coolant;
• limiting, by the electronic control unit, circulation of the coolant at starting the internal combustion engine;
• circulating, by the electronic control unit, the coolant preferentially through the second flow passage via control over the adjusting means based on the measured temperature in a period in which circulation of the coolant is limited;
• and
• prohibiting circulation of the coolant before the coolant is circulated preferentially through the second flow passage by the electronic control unit.