U.S. Investigators Find Possible “Defeat” Software In Mercedes Diesels

Potentially illegal software mods have been found on Mercedes-Benz diesel models by U.S. investigators, mods that would help the cars pass emissions testing.

According to German paper Bild am Sonntag, investigators found engine management function called “Slipguard”, programmed to recognize whether the car was being tested in a laboratory.

Citing official documents, the paper also claims that another functioned called “Bit 15” was there to switch off emissions cleaning after about 16 miles (25 km) of driving. Apparently, the software helped reduce the application of AdBlue fluid, which helps eliminate harmful exhaust gases, resulting in some Mercedes diesels emitting NOx fumes up to 10 times higher than the legally permitted levels.

The German newspaper report cited e-mails from Mercedes‘ own engineers who questioned whether these software functions were legal. According to Autonews, a spokesman for Daimler declined to comment on the findings, stating that the automaker was fully cooperating with U.S. authorities.

“The authorities know the documents and no complaint has been filed,” said the spokesman. “The documents available to Bild have obviously selectively been released in order to harm Daimler and its 290,000 employees.”

Back in 2016, a class action lawsuit was filed against Mercedes by owners of their diesel-powered cars in the U.S., claiming that the automaker “deceived customers by knowingly programming its BlueTEC vehicles to release illegal levels of emissions in virtually all real world driving conditions.”

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  • Bash

    What if…. Everybody…. simply does it.

    • Ermal Morina

      ikr. I’m wondering if every car manufacturer has some kind of software for their diesels,it just hasn’t been discovered yet by authorities.
      It is really plausable imo

    • Six Thousand Times

      This has been generally supposed for a while. Now, some proof comes to light.

  • SteersUright

    These particulates are particularly evil, known to lodge in the lungs of people everywhere, and there’s a reason the US and EU targeted NOx emissions so aggressively. That the Germans tried to circumvent and cheat, dirtying the air their own children will breath and to the extent of several hundred times the claimed emissions, is beyond reproach and simply vulgar. VW was fined way too lightly and the fact that most of their higher up executives could simply walk away without jail time further exemplifies the divide in our societies, with some simply being too rich to jail. I hope BMW and MB are prosecuted much more aggressively, and even GM, who was believed to be cheating as well. Only when executives learn that they too face uncompromising consequences for breaking laws and harming society, will they ever lead their companies with cultures of higher moral standards.

  • LJ

    Why name it something devious like “Slipguard”?

    Name it “There’s nothing to see here”.

  • izzey04

    Blame all this on the Europe’s climate change dogma….

    • LeStori

      Blame it on the Save the Worlders. Killing us with toxicity whilst reducing climate change CO2 using inappropriate technology.

  • LeStori

    The real problem is Governments should not have encouraged the use of Diesel for consumer vehicles. Just as they are now “funding” consumer purchase of EVs in many countries. Unfortunately many Goverments kow towed to the screams of the “save the World crowd”. The rest of us just went along on the toxic ride.

    • Six Thousand Times

      So you’re against saving the world? Or just enjoying the conspiracy fantasies more…?

  • LeStori

    Nothing wrong with the engineering. The real problem is governments needing to react to the squeakiest wheel. In this case the Save the world brigade. This led to many governments encouraging people to buy Diesel. A technology not really suited for everyday consumer vehicles. Today the fashion is EVs. Wonder what toxic delights will result…



    Might as well look into every diesel powered vehicle at this point just be certain.

  • dean

    too bad for you, my new s class has diesel particulate filter in the a/c, so I dont worry about what the peasants breath, and at home I only breath the air of the himalayas brought to me by vestal virgins riding on unicorns

    • brn

      but what do those that can only afford a C-class do?

      • dean


        • brn