As soon as one kind of diesel car exhaust post-processing system medicament automatic identification induction installment, including a medicament storage tube, supposes on the medicament storage tube week wall the medicament perceptron, one and the medicament perceptron electric interlock pours into the control unit, one and pours into measuring appliance of caution light the control unit electric interlock, states the medicament perceptron including a fluid position sensory element as well as an ohm gage, when pours into the medicament peroxide solution resistance nature preinstall of for the ohm gage, and the liquid level arrives at preinstall of position time highly the fluid position sensory element, then to pours into the signal transmission the control unit, causes the measuring appliance caution light extinguishment, and pours into the control unit at the right moment  to move the actuating unit, medicament peroxide solution spraying in exhaust pipe, with nitrogen oxygen compound electronation reaction; If resistance of nature the detection is not correct time, then to pours into the signal transmission the control unit, then the control instrument caution light shines the warning, increases the correct medicament peroxide solution until the driver, takes advantage of this guaranteed that the driver increases the correct medicament.