Automatic Test System For Engine ECU Based On LabVIEW

With the rapid development of China’s automobile industry， they areincreasingly emphasized the importance of independent research and development.There are two technical problems in front of us， one of them is the enginetechnology， and the other is the electronic control technology (ECU).User hope thecar become much more comfortable and intelligent. The engine electronic control unitfunctions become very complicated and the diagnosis of the various functions of theelectronic control unit are becoming more and more difficult. Most developers have tomanually debug the function of the ECU modules.The development work hasbecome very heavy by this way. Based on this situation， the development of theAutomatic Test System for ECU is a very meaningful work.The diagnosis of the various functions of the electronic control unit is an veryimportant work at the development phase of the engine electronic control unit， theefficiency and reliability Which directly affects the ECU development time. Thisarticle According to the specific test requirements， designed an engine electroniccontrol unit automatic test system. This article did lots of work from the overallframework of the automatic test system and the signal path， in addition， LabVIEWprogram design is the focus of this article.Engine ECU test requires the system itself must has a certain degree offlexibility， the requirements of the characteristics， we chosen the virtualinstruments， its advantages will be described in this article.LabVIEW program is the main work of this paper. And the major work issummarized as the following sections.First of all， the hardware， according to the characteristics of the engine ECUsignal， we divided all the signals into seven kinds of group. They are AD， SW，SIN， PWM， LS， Injector actuator signal and ignition coil signal. They have theirown test methods and signal test loop.Followed by the software part， the test system needs to achieve automaticcontrol of external equipment， automatically switched the test loop， real-time display and save the result of the test data， So the main work of this paper can bedivided into the following sections.(1)System sends SCPI commands to controlAgilent device via VISA module.(2)Real-time display of test data. The source of testdata is mainly come from three parts. The first category is the CAN messageThe second category is returned by the Agilent34980A internal DMM voltagedata. The third category is the injection actuators and ignition coil waveform datawhich returned by the oscilloscope.(3)After the processing of the data analysis displayand storage is synchronized， the test data is stored in Excel， to facilitate the userplayback data， for the next step of analysis.The system’s usability has been proved In the process of debugging， it has highperformance， accurate measurement， less time-consuming features， fully capableof the ECU testing work has practical value in the diagnosis of the engine ECU.