According to Bild am Sonntag, the California Air Resources Board (CARB) has found software lurking with the automatic transmissions bearing the internal code AL55 and used with the company's V6 engines.
The defeat device on the transmission reportedly uses the absence of an movement of the steering wheel to infer that the car is undergoing a laboratory emissions test. In that scenario, the transmission engages a gear shifting program or "warm up strategy" that's designed to reduce fuel consumption and, therefore, the amount of carbon dioxide emitted.
Above and below: First-generation Audi Q5.
Neither CARB nor Audi have responded to requests for more information. It's not clear whether this defeat device software was used only on cars sold in the US, nor is it known how many cars are affected.
Bild claims that Audi stopped using the software in mid-2016, and that several technicians, deemed to be responsible, have been suspended.
Transmissions with this software were said to be used on various models in the US, including A6, A8 and Q5. With 38,967 Q5s sold this year through to the end of October, the Q5 is the brand's most popular car in the States.
This device, if confirmed, seems to be unrelated to the various pieces of software that were used on the Volkswagen Group's EA189 diesel engine family, and which were used to produce legal NOx emissions only during laboratory testing.
The so-called Dieselgate scandal involves around 11 million vehicles worldwide, and will cost the company up to US$14.7 billion in fines and compensation in the US alone.
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