The LV 124 and LV 148 standards are a series of tests describing how to subject the automotive ECUs to electrical disturbances, that simulate those in an automobile’s electrical system during driving. These disturbances vary from transient power supply changes, to extremely short pin interruptions ans short circuits and they simulate events like engine start, cable breakage or idle behaviour of the certain components.
The purpose of these standards is to improve the electrical (and overall) safety of the ECUs, under all driving circumstances. One can surely say that the level of component safety will define the autonomy level.Given the fact that the newest autonomous driving trend relies on 100% safety, testing according to these standards becomes crucial.
The LV 124 and LV 148 standards where put together by German OEMs, but have nowadays several variations for almost all car manufacturers around the globe, VW 80000, BMW GS 95024-2, VDA 320 , BMW GS 95026, VW 82148, MBN LV 124 etc. and it even ISO standardized as ISO 16750. These standards differ only slightly in the complexity of the defined waveforms and in the required rise and fall times of the interruptions.
For a while many OEMs struggeled to perform these tests manually. Due to the rising complexity of the automotive ECUs and the pressure created by shorter times-to-market, the manual test becomes an impossible task to achieve and one which should not be pursued. According to automobile safety reports, many electronic equipment failures which cause accidents, are due to human error during testing phases.
We can say that by lowering the human error, we will lower the failure rates.
That makes the automated testing according to LV 124 / LV 148 a must for achieving autonomous driving safety goals.
There are many challenges when testing according to these norms. For all of them, WKS Informatik developed the best solutions on the market!
Moreover WKS Informatik developed the first generic fully-automated testing system for LV 124 / LV 148, RTStand LV 124 (www.lv124-rtstand.com), removing the human factor, enabling more indepth data analysis, automated reporting and offering testing capabilities for all kinds of automotive ECUs with just one system!
1.Monitoring & Logging
The first challenge is the requirement to monitor ALL ECU pins, before, during and after the stimulation. Oscilloscopes have way too less channels than the ECUs have and usual DMMs lack the ability to distinguish between “good” and “bad” data. Moreover, testers usually have to improvise in order to measure current over the whole range of the ECU activity.
WKS Informatik’s Tube Analyzer (www.tube-analyzer.com) is a solution for all these problems.