A coolant pump for pumping a coolant for an internal combustion engine in a vehicle comprising the internal combustion engine and a central engine control unit, said coolant pump comprising: a pump shaft which is rotatably mounted in a pump housing and which is driven by the internal combustion engine via a belt drive, an impeller which is arranged on the pump shaft and accommodated in a pump chamber of the pump housing, pumping a coolant, an axial piston pump which is actuated via a wobble plate on a rear side of the impeller and which branches-off a fraction of the pumped coolant, a hydraulic circuit which extends from the axial piston pump via a proportional valve back to the pumped coolant and which includes a branch between the axial piston pump and the proportional valve as a hydraulic actuator, a regulating slide valve which adjusts the volume flow of the coolant pumped by the coolant pump and which is slidable depending on a pressure in the hydraulic circuit, a position sensor which detects a position of the regulating slide valve indicative of the volume flow of the pumped coolant and which outputs an actual value signal of the position of the regulating slide valve, characterized in that the coolant pump comprises a pump control of its own which controls the proportional valve in the hydraulic circuit on the basis of the actual value signal from the position sensor and a target value signal from the central engine control unit, wherein the desired value signal indicates i) a predetermined position of the regulating slide valve or ii) a predetermined volume flow and the speed of the internal combustion engine or coolant pump; and the pump control and the position sensor are formed as a mutual electronic component. a pump shaft which is rotatably mounted in a pump housing and which is driven by the internal combustion engine via a belt drive, an impeller which is arranged on the pump shaft and accommodated in a pump chamber of the pump housing, pumping a coolant, an axial piston pump which is actuated via a wobble plate on a rear side of the impeller and which branches-off a fraction of the pumped coolant, a hydraulic circuit which extends from the axial piston pump via a proportional valve back to the pumped coolant and which includes a branch between the axial piston pump and the proportional valve as a hydraulic actuator, a regulating slide valve which adjusts the volume flow of the coolant pumped by the coolant pump and which is slidable depending on a pressure in the hydraulic circuit, a position sensor which detects a position of the regulating slide valve indicative of the volume flow of the pumped coolant and which outputs an actual value signal of the position of the regulating slide valve, characterized in that the coolant pump comprises a pump control of its own which controls the proportional valve in the hydraulic circuit on the basis of the actual value signal from the position sensor and a target value signal from the central engine control unit, wherein the desired value signal indicates i) a predetermined position of the regulating slide valve or ii) a predetermined volume flow and the speed of the internal combustion engine or coolant pump; and the pump control and the position sensor are formed as a mutual electronic component.