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Catching defeat devices: How systematic vehicle testing can determine the presence of suspicious emissions control strategies

While the Dieselgate scandal raised awareness of defeat devices—software calibrations that manipulate pollutant emission controls when vehicles are in the real world—third-party evaluation remains difficult because these devices are embedded in sophisticated computer code. To aid in detection by governments and third parties, this new white paper offers a practical, seven-step methodology that uses vehicle testing to determine the presence of an inappropriate calibration change. To illustrate, the authors test for devices that manipulate NOx levels in exhaust and use two Mercedes-Benz C-Class Euro 6b vehicles as demonstration vehicles—the diesel versions of a C180 and C200.