It's not the same situation as Volkswagen's though.
When Volkswagen was outed for its emissions-cheating diesels, we knew it couldn't be the only carmaker to have done this. In a report by Bloomberg, a federal lawsuit was filed against Mercedes-Benz that accused the automaker of using a defeat device in its BlueTec cars. The lawsuit, which was filed in New Jersey, claims that Mercedes-Benz's cars turn off its pollution controls at ambient temperatures below 50 degrees Fahrenheit.
This allows the diesel cars to emit far more than the legal limit of nitrogen oxide and other pollutants. The lawsuit claims that the diesel-powered ML350, ML320, S-Class, E-Class and GLE are among the affected cars. Daimler spokesman Joerg How told Bloomberg that the claims are "baseless," and that "all of our vehicles comply with regulatory framework." Unlike Volkswagen's current situation, the lawsuit against Mercedes-Benz was brought by an owner in Illinois and filed by a law firm based in Seattle, Washington. The law firm states its allegations are based on an article that was published in German magazine Der Spiegel.
The magazine had claimed that Mercedes-Benz admitted to engineering the affected vehicles to shut off emissions controls in cooler ambient temperatures to protect the engine, reports Bloomberg. The law firm also cites an independent test that was done in Europe that found that a diesel-powered Mercedes-Benz emitted more nitrogen oxide in real-world driving than the car did in laboratory testing. "Mercedes never disclosed to consumers that Mercedes diesels with BlueTec engines may be 'clean' diesels when it is warm, but are 'dirty' diesels when it is not," the lawsuit states.
"Mercedes never disclosed that, when the temperature drops below 50 degrees, it prioritizes engine power and profits over people." It's unclear whether the lawsuit against Mercedes-Benz will lead to the same actions as Volkswagen is currently facing, but the firm filing the lawsuit hopes to turn it into a nation-wide class-action suit. Just last week, Mercedes-Benz's parent company Daimler AG revealed that it would invest roughly $3 billion in updating the emissions control devices on its diesel-powered cars. That makes it seems like Mercedes-Benz knew about the problem and was trying to nip it in the bud before it got out.