Adding Unified Diagnostic Services over CAN to an HIL Test System 2011-01-0454
The increase in the number of electronic control units (ECUs) in the modern vehicle, combined with increased software complexity and more distributed controls has led to an extreme testing challenge when it comes to the verification and validation of body-control ECUs. In general test engineers have to deal with more software configurations, more closed-loop interaction between ECUs, and more fault conditions than ever before.
By adding Unified Diagnostic Services (UDS) over CAN to a Hardware-In-The-Loop (HIL) test system, Lear was able to increase test automation and provide wider test coverage by automating the ECU flashing process, adding diagnostic identifiers and trouble codes to their test scripts, and providing a quick and easy way to exercise ECU I/O.
Lear chose to implement their HIL testers on the open PXI hardware platform, utilizing National Instruments' VeriStand software framework. A main reason for selecting NI VeriStand was the ability to add custom functionality using NI LabVIEW, allowing Lear to integrate hardware from multiple vendors and add support for UDS (ISO-14229.1)
This paper will discuss in detail the process for automating ECU flashing and including diagnostic data for more comprehensive test scripts, as well as the implementation of the Unified Diagnostic Services via the Automotive Diagnostic Command Set for LabVIEW.