Method and system for determining, via sensor network, position of GNSS receiver arranged in a motor vehicle intentionally is impaired in a targeted manner by interference source. Sensor network includes traffic route points having at least one sensor to detect a presence of interference source. Method includes detecting, as motor vehicle passes one of traffic route points, an interference signal emitted by interference source and/or a received signal of GNSS receiver impaired by interference source by the at least one sensor of the one traffic route point; processing the detected signals to establish whether interference source is present in passing motor vehicle; and when the presence of interference source established, generating information that signals at least a location of the one traffic route point and the interference source in the motor vehicle. A position of the motor vehicle is determined from the location of the traffic route point.