A diagnostic system for identifying vehicle sensors impaired by a foreign substance. The system includes a plurality of vehicle sensors configured to facilitate navigation of a vehicle in an environment. A gear shift detection sensor is configured to detect a gear position of the vehicle. A control module is configured to identify which of the plurality of vehicle sensors is impaired by a foreign substance; and identify for an operator of the vehicle which of the plurality of vehicle sensors is impaired due to the foreign substance based on the gear position of the vehicle.