A vehicle environment detection system (2) including a control unit (4) and a sensor arrangement (3) that in turn includes at least two sensor arrangement parts (3a, 3b). The control unit (4) is arranged to determine one or more systematic errors in a certain direction (9, 10) for one sensor arrangement part (3a, 3b) by combining acquired sensor data for the sensor arrangement part (3a, 3b) with acquired sensor data from another sensor arrangement part (3b, 3a). The another sensor arrangement part (3b, 3a) has a lower degree of systematic error in the certain direction (9, 10) than the sensor arrangement part (3a, 3b).