Design of CAN-BUS based computer interfaced diagnostic device for some special purpose heavy duty vehicles

Nowadays, heavy duty vehicles with diesel engines are used in many special applications. Applications such as, cranes, fire trucks, sewage trucks, concrete pumps, garbage trucks, agricultural machinery and construction machinery are some of these. In special purpose heavy duty vehicles, apart from the powertrain system such as engine, transmission and steering system, there is a section called superstructure and produced according to special function of the vehicle. There are many systems on the superstructure such as vehicle water pumps, concrete pumps, hydraulic pumps, valve groups, user displays, input and output modules, various sensors and superstructure control processor. These systems receive the driving power from the vehicle engine and the electrical energy from the vehicle battery. In special purpose heavy duty vehicles, communication between the electronics systems of superstructure and the vehicle electronics control unit (ECU) is provided by the Control Area Network (CAN) communication system. While vehicle powertrains use the Society of Automotive Engineers (SAE) J1939 protocol for communication, superstructure systems use CANopen protocol. Due to increasing electronics systems, the number of malfunctions that may occur on vehicles is increasing, and detection of malfunctions is becoming increasingly difficult. A diagnostic device that specifically produced for the vehicle emerges as an necessity for fault detection. In this study, an electronic device that can read various fault conditions and data over the CAN lines of special purpose heavy duty vehicles was designed. There are two CAN lines on the device. While one of the lines is connected to the CAN line of the chassis vehicle that the powertrains are located, the other CAN line is connected to the CAN line that superstructure electronic systems are located. The obtained data is tansferred to the user through the computer interface. The aim of this device to detect malfunctions easily, reduce maintenance times and costs.