Leak detection method of reducing agent pumping system

Lines formed as the reducing agent tank, an injector, wherein the reducing agent tank and the injector according to the present invention, and the leak detection method of the reducing agent injection system comprising a pump module, which is installed on the line, the pump of the pumping module to the injector pumped and, if it is determined that more than the step of sensing a pressure, the pressure that is detected first set value, and generating a pressure decrease warning signal, when the pressure sensed is greater than the first set value, greater than the first set value 2 If it is determined to be smaller than the set value, the step of setting the pump is operating in the load over, the operation steps to stop the operation of the injector, a heater for heating a reducing agent of the pumping module for a set period of time, and reducing the temperature of the pumping module, If it is determined it is lower than the set value, that a leak has occurred in the line between the pump module and the injector It may comprise determining a.