OnBoardDiagnostics 2 (OBD2) is a diagnostic device designed for advanced public transport vehicles, such as buses, trolleybuses and trams, provided with CAN bus.
The main function of OBD2 is to show to vehicle operators information on defects detected in vehicle. Vehicle subassemblies, communicating with each other through CAN bus, send between each other information regarding possible problems in their functioning. The task of OBD2 is interception of this information, descrambling it to a form understood by the user (e.g. driver, vehicle mechanic), presentation in a legible and clear way on the display and saving to a file a register for the needs of future analysis. Due to this fact, the device is equipped with 2 or 4 CAN interfaces, clear graphic display and comfortable keyboard.
OBD2 records parameters that are important for safety, continuous and effective work of the vehicle, including: fuel usage, engine and transmission temperature, engine speed, vehicle speed, driving dynamics, energy used (trolleybuses, trams), etc.
Information that is gathered and analyzed is supposed to improve functioning of the fleet in a transport enterprise; it also can be helpful during repair of possible failures at the stage of service work. OBD2 makes possible control of external devices, i.e.: passenger counting gates (with a possibility of recording measurement results), monitoring (set of cameras with recorder), GPS receiver.
The majority of parameters configuring OBD2 operation is contained in the data, which is programmed to internal memory of the device. They include the range of vehicle parameter registration, information about codes and description of defects reported by subassemblies communicating via CAN bus, menu and data language, and a set of fonts. Programming and downloading of register files can be done remotely with the use of radio modem, Bluetooth modem or GSM/GPRS/UMTS modem, which provides a decentralized control method of fleet operation of a transport enterprise.