The cars subject to update will be mostly those equipped with Euro-5 and partially with Euro-6 emission class engines, what will allow to reduce nitrogen oxides emissions by 25-30 percent, according to the VDA press release.
The figures reportedly include 2.5 million of Volkswagen cars that have already been set for upgrade. The cars produced by BMW, Daimler, Opel and Volkswagen are supposed to be refit after an approval of the Federal Motor Transport Authority (KBM), according to the press release.
The software updates will not incur any costs on the car owners and will not affect engine servicing or fuel consumption, the press release specified.
In July, the Spiegel magazine reported that Volkswagen, Audi, Porsche, BMW, and Daimler, as well as other leading German automakers, coordinated their actions on designing diesel emissions treatment systems in diesel vehicles. The media added that the companies had colluded to rig the size of tanks for AdBlue liquid, making it smaller and ultimately preventing effective emission treatment.
The so-called diesel scandal, in which Germany's Volkswagen was involved, dates back to 2015, when the US Environmental Protection Agency (EPA) accused the company of using cheating emission software for its diesel cars. The company admitted that 11 million of its vehicles worldwide had been fitted with emissions cheating software and agreed to pay settlements amounting to $15 billion.