Whether large or small, a truck fleet operator has to know the locations of its vehicles in order to best manage its business. On a day to day basis loads need to be delivered or picked up from customers, and other activities such as vehicle maintenance or repairs have to be routinely accommodated. Some fleets use aftermarket electronic systems for keeping track of vehicle locations, driver hours of service and for wirelessly text messaging drivers via cellular or satellite networks. Such aftermarket systems include GPS (Global Positioning System) technology, which in part uses a network of satellites in orbit. This makes it possible for the fleet manager to remotely view the location of a vehicle and view a map of its past route. These systems can obtain data directly from vehicle sensors or from the vehicle network, and therefore report other information such as fuel economy. The fleet manager can receive alerts when high-level brake applications occur, which could be an indication of tailgating or aggressive driving behavior. Undesirable equipment issues or driver performance concerns can diminish safety and fuel efficiency, so identifying them is important.Various manufacturers provide competing systems in the North American market geared to providing information that is useful to their customers. Qualcomm Enterprise Services (Qualcomm) is one such manufacturer. Qualcomm systems on three separate highway tractors were tested in this research. The reason for doing so was to establish if Qualcomm data from an accident-involved vehicle could be useful to the collision investigation community in understanding what happened. The GPS aspect of the data was of particular interest since built-in vehicle systems can provide speed, brake and clutch data plus other information but they do not record geographical position.Independent physical evidence that helps explain the position-time history of a vehicle is extremely valuable to a motor vehicle collision investigator attempting to reconstruct a crash. It could be incorporated with other physical evidence such as vehicle damage, accident site tire marks and pavement scars to help determine how an accident occurred.