What software-related defect led Volkswagen to recall diesel cars during the 2015 emissions scandal?
Answer
Defeat-device software
Defeat-device software led Volkswagen to recall diesel cars during the 2015 emissions scandal.
Volkswagen installed software in certain diesel vehicles that could recognize when the cars were undergoing official emissions testing. During those tests, the software activated emissions controls more strongly than it did during ordinary driving. Real-world nitrogen oxide emissions were therefore much higher than the laboratory results suggested.
The United States Environmental Protection Agency issued a notice of violation in September 2015, and Volkswagen acknowledged using the software. The affected vehicles were commonly described as “clean diesel” models and used engines from the company’s EA189 diesel family. Recalls and technical fixes followed in several countries.
The defect was not a conventional broken mechanical part. It was deliberate programming intended to manipulate testing results, which is why the software is called a defeat device. The scandal led to fines, lawsuits, buybacks and lasting changes in diesel-emissions testing.