A driver assistance system of a vehicle includes a vision sensor and a non-imaging sensor sensing forward of the equipped vehicle. The control, responsive to processing of captured image data and to processing of captured sensor data, provides a driver assistance function. The control, via to processing of captured image data and captured sensor data, detects the presence of vehicles. The control may disable at least part of the driving assistance function at least in part responsive to the control detecting a vehicle via one of (i) processing of image data captured by said vision sensor or (ii) processing of sensor data captured by the non-vision sensor, and failing to detect that detected vehicle via the other of (i) processing of image data captured by said vision sensor or (ii) processing of sensor data captured by the non-vision sensor.