Vehicle Diagnostic Monitoring System ARSLAN SHAHID ARSLAN TARIQ FAISAL M. SALEEM Abstract Vehicle Diagnostic Monitoring System is a new dimension in the field of Automobiles. It consists of an On-Board Diagnostic System which is a core element of all the modern day vehicles, and a communication system. This system collects the data from the vehicle’s On-Board Computer; ECU (Electronic Control Unit) and sends it to a remote location through a GSM modem, to monitor the performance and maintain statistics. This system can enhance Vehicle’s performance by periodic inspections from remote locations. Vehicle Diagnostic Monitoring System comprises of two parts. The first part is the data acquisition circuit and will be connected to the Vehicle’s OBD-II interface. It will get data from the OBD-II system by using some commands and then will convert the returned hex values to easily understandable form. The converted values will then be displayed on an in-vehicle display unit. Next it will send this data to the second part of the project, the communication circuit through serial interface. This circuit comprises of a GSM modem. The GSM modem will then send this data to a remote location over the air through SMS. This project will provide advantage to both, the vehicle owner and the vehicle manufacturer. The vehicle owner can inspect his Vehicle from remote locations and can have all the information about his vehicle no matter where he is. The Vehicle Manufacturers can analyze the performance of their vehicles from remote locations and thus can know the pros and cons of different systems being used in the vehicle. They can improve their future vehicle models on the basis of this feedback. ii Table of Contents 1 Introduction ........................................................................................................................................................... 1 1.1 Block Diagram of Vehicle Diagnostic Monitoring System.......................................................................... 2 2 Technical Background .......................................................................................................................................... 4 2.1 On-Board Diagnostic System ....................................................................................................................... 4 2.1.1 OBD-I .................................................................................................................................................. 4 2.1.2 OBD-1.5 .............................................................................................................................................. 4 2.1.3 OBD-II ................................................................................................................................................. 4 2.2 The OBD-II .................................................................................................................................................. 4 2.3 OBD-II Protocols ......................................................................................................................................... 5 2.4 Identifying the OBD-II Protocol .................................................................................................................. 6 2.5 OBD-II Codes [5] ......................................................................................................................................... 6 2.6 ISO 9141-2 ................................................................................................................................................... 6 2.6.1 Protocol Initialization [16] ................................................................................................................. 7 2.7 Controller Area Network (CAN) .................................................................................................................. 7 2.7.1 Working of CAN [17] .......................................................................................................................... 8 2.7.2 Types of Data Frame [17] ................................................................................................................... 9 Table 2.2 Extended CAN ........................................................................................................................................ 10 2.8 GSM ........................................................................................................................................................... 10 2.9 The SIM-300 DZ GSM Module ................................................................................................................. 12 2.9.1 Key Features of SIM-300 DZ ............................................................................................................ 13 2.9.2 SIM-300 DZ Pin Out ......................................................................................................................... 14 2.10 AT Commands ........................................................................................................................................... 16 2.10.1 Basic AT Commands: ........................................................................................................................ 16 2.10.2 Extended AT Commands: .................................................................................................................. 16 2.11 PIC Microcontrollers .................................................................................................................................. 16 2.11.1 PIC18F4580 ...................................................................................................................................... 17 2.12 MCP2551 ................................................................................................................................................... 18 2.13 ELM327 [10].............................................................................................................................................. 18 2.13.1 ELM327 Functionality [10] .............................................................................................................. 19 iii 2.14 MAX232 .................................................................................................................................................... 20 2.15 Liquid Crystal Display ............................................................................................................................... 22 2.16 PIDs (Parameter IDs) [16] ......................................................................................................................... 24 3 Design & Implementation ................................................................................................................................... 25 3.1 Technical Block Diagram of Vehicle Diagnostic Monitoring System ....................................................... 25 3.1.1 The Data Acquisition Circuit ............................................................................................................. 26 3.1.2 Processing, Display and Communication Circuit ............................................................................. 28 3.2 Flow Chart of the Microprocessor Code .................................................................................................... 30 3.3 Server Side Software .................................................................................................................................. 32 4 Results ................................................................................................................................................................. 34 4.1 Results ........................................................................................................................................................ 34 4.1.1 Diagnostic Trouble Codes ................................................................................................................. 34 4.1.2 Real Time Data .................................................................................................................................. 34 4.1.3 Freeze Frame Data ........................................................................................................................... 34 4.1.4 Clearing Diagnostic Trouble Code ................................................................................................... 34 4.2 Server Side Database.................................................................................................................................. 38 5 Conclusion and Future Enhancements ................................................................................................................ 39 5.1 Conclusion ................................................................................................................................................. 39 5.2 Future Enhancements ................................................................................................................................. 40 References: .................................................................................................................................................................. 41 Appendix A: C Source Code ...................................................................................... Error! Bookmark not defined. Appendix B: PCB Design ..........................................................................................