System and method for diagnosing lack of coolant of vehicle to which integrated thermal management valve is applied

Abstract

A system for diagnosing lack of coolant of a vehicle to which an integrated thermal management valve is applied according to the present disclosure includes an integrated thermal management valve including a plurality of valves which are openable and closable, and configured to selectively distribute coolant introduced from a head of an engine to front ends of a radiator, a heater, and an oil cooler, a coolant temperature sensor installed on each of a coolant inlet, a coolant outlet, and a block of the engine and configured to measure a temperature of the coolant, and a control unit configured to determine whether the coolant is insufficient by monitoring a decrease amount of a coolant temperature difference measured from the block and the coolant outlet, and finally determine whether the coolant is insufficient by accumulating an increase amount of a temperature difference between the coolant outlet and the coolant inlet.

1 . A system for diagnosing lack of coolant, the system comprising:
 an integrated thermal management valve including a plurality of valves which are openable and closable, and configured to selectively distribute coolant introduced from a head of an engine to front ends of a radiator, a heater, and an oil cooler;   a controller configured to receive valve opening and temperature information from the above integrated flow control valve and coolant temperature sensor, and configured to determine whether the coolant is insufficient by monitoring a decrease amount of a coolant temperature difference measured from the block and the coolant outlet as a valve on an outlet side connected to the radiator is open, and finally determine whether the coolant is insufficient by accumulating an increase amount of a temperature difference between the coolant outlet and the coolant inlet;   wherein the controller determines that the coolant is insufficient when it is determined that the coolant temperature difference measured from the block and the coolant outlet is lower than or equal to a set temperature.   wherein the controller continuously monitors an increase amount of the temperature difference between the coolant outlet and the coolant inlet when it is determined that the coolant is insufficient, and finally determines that the coolant is insufficient when it is determined that an accumulated factor value is greater than or equal to a set comparison value by accumulating different factor values for each continuous temperature difference.   
     
     
         2 . The system of  claim 1 ,
 wherein the control controller determines whether the coolant is insufficient as a valve on an outlet side connected to the radiator in the integrated thermal management valve is open due to an increase in the coolant temperature.   
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . A method of diagnosing lack of coolant, the method comprising:
 a first operation of determining whether a valve on a radiator side constituting an integrated thermal management valve is open;   a second operation of measuring a coolant temperature through a coolant temperature sensor installed on each of a coolant outlet and a block of an engine as the valve on the outlet side is open;   a third operation of determining, by a controller, whether coolant is insufficient by monitoring a decrease amount of a coolant temperature difference measured from the block and the coolant outlet;   a forth operation of calculating, by the controller, an increase amount of a temperature difference between the coolant outlet and a coolant inlet when it is determined as a state in which it is determined that the coolant is insufficient; and   a fifth operation of accumulating the increase amount of the calculated temperature difference between the coolant outlet and the coolant inlet as a factor value by continuously performing the third operation, and finally determining, by the controller, whether the coolant is insufficient using the accumulated factor value.   wherein in the fifth operation, when it is determined that the factor value accumulated through the forth operation is greater than or equal to a set comparison value, it is finally determined that the coolant is insufficient.   
     
     
         6 . The method of  claim 5 ,
 wherein in the second operation, whether an initial condition for determining whether the coolant is insufficient is satisfied is determined by measuring traveling environment information in the state in which the valve on the outlet side is open before measuring the coolant temperature through the coolant temperature sensor.   
     
     
         7 . The method of  claim 6 ,
 wherein the initial condition includes RPM information of the engine, inclination information at which a vehicle is positioned, and outside air temperature information of the vehicle.   
     
     
         8 . The method of  claim 5 ,
 wherein in the third operation, when it is determined that the coolant temperature difference measured from the block and the coolant outlet is lower than or equal to a set temperature, it is primarily determined that the coolant is insufficient.   
     
     
         9 . (canceled) 
     
     
         10 . The method of  claim 5 , further comprising: a sixth operation of transmitting, by the controller, coolant lack information to a driver when it is finally determined that the coolant is insufficient in the fifth operation, and transmitting a control signal for proceeding to a fail-safe mode to the integrated thermal management valve.