Cooling device for vehicle

A cooling apparatus for a vehicle, the cooling apparatus including a first coolant circuit in which coolant circulates through an engine and a second coolant circuit in which coolant circulates without passing through the engine, the cooling apparatus comprising:

• a valve that, when closed, decreases or zeroes out the flow rate of the coolant in the first coolant circuit that passes through the engine, and, when open, the valve mixes the coolant in the first coolant circuit and the coolant in the second coolant circuit;
• a first coolant temperature sensor for detecting the temperature of the coolant in the first coolant circuit;
• a second coolant temperature sensor for detecting the temperature of the coolant in the second coolant circuit;
• and
• a valve control section for closing the valve when the temperature of the coolant in the first coolant circuit is less than a half-warm-up determination value set to a value lower than a determination value for warm-up completion of the engine, the valve control section opening the valve when the temperature of the coolant in the first coolant circuit increases to the half-warm-up determination value or higher,
• wherein, if a failure has occurred in one of the first coolant temperature sensor and the second coolant temperature sensor, the valve control section opens the valve to mix the coolant in the first coolant circuit with the coolant in the second coolant circuit.

A cooling apparatus for a vehicle, the cooling apparatus including a first coolant circuit in which coolant circulates through an engine and a second coolant circuit in which coolant circulates without passing through the engine, the cooling apparatus comprising:

• a valve that, when closed, decreases or zeroes out the flow rate of the coolant in the first coolant circuit that passes through the engine, and, when open, the valve mixes the coolant in the first coolant circuit and the coolant in the second coolant circuit;
• a coolant temperature sensor for detecting the temperature of the coolant in one of the first coolant circuit and the second coolant circuit;
• a coolant temperature estimating section for estimating the temperature of the coolant in the other one of the first coolant circuit and the second coolant circuit;
• and
• a valve control section for closing the valve when the temperature of the coolant in the first coolant circuit is less than a half-warm-up determination value set to a value lower than a determination value for warm-up completion of the engine, the valve control section opening the valve when the temperature of the coolant in the first coolant circuit increases to the half-warm-up determination value or higher,
• wherein, if a failure has occurred in the coolant temperature sensor, the valve control section opens the valve to mix the coolant in the first coolant circuit and the coolant in the second coolant circuit.