Daimler Accused of Diesel Cheat Device Software

Environmental activists are claiming new evidence that German automaker Daimler has been using illegal emissions “defeat devices” embedded in vehicle software.

The lobby group Deutsche Umwelthilfe (DUH) claims its expert witness’s report identifies eight previously unknown defeat devices on an Euro 6 compliant Mercedes E-Class model. His report suggests the car ends up emitting 500 times the nitrogen oxide levels in real world driving than those measured in laboratory conditions by the automaker. However, the German regulator, the Federal Motor Transport Authority (KBA), says the findings are erroneous.

Automotive software expert Felix Domke, commissioned by the US legal firm Milberg, documented a total of eight previously unknown defeat devices in a single 2016 Mercedes-Benz E 350 BlueTEC 4MATIC. In DUH’s view, these defeat devices reduce the effective purification of exhaust gases by the SCR catalytic converter. Until now, Daimler has always denied using illegal defeat devices in diesel cars sold in Germany and Europe.

Domke measured data from the vehicle with an OM642 3.0-liter six-cylinder engine claiming 250bhp, first registrered in January 2016. The built-in engine control unit’s calibration data was also analyzed. The measurement data from the engine control unit during real driving operation was subsequently correlated with the calibration data.

His study claimed to have found defeat devices and documented them in detail. Six of these are associated with the selective catalytic reduction (SCR) system. Three of them depend on an “ageing factor” that significantly lowers the thresholds at which the shutdown devices activate. In two cases, this already begins after only a few thousand kilometers, just one percent of the vehicles expected lifecycle. A further reduction occurs after the vehicle has aged by approximately 20%. Two defeat devices claimed to be found are linked to the vehicle’s exhaust gas recirculation system.

In a statement, Domke who served as an expert witness at the parliamentary enquiry committee into the Volkswagen emissions scandal in 2017, said: “The defeat devices found activate in driving situations that are common in road use conditions. Even under normal driving conditions, at least one defeat device almost always actively prevents the improvement of emissions, even if it is not physically necessary or necessary for engine protection. This significantly reduces the amount of AdBlue injected, which is urgently needed to neutralize the nitrogen oxides in the SCR catalytic converter; similarly, the exhaust gas recirculation rate is reduced. As a result, the normally effective exhaust gas treatment hardware often only performs at a fraction of its potential capacity and the vehicle emits unnecessarily large amounts of nitrogen oxides.”

Glenn Phillips, managing partner of Milberg, said: “From a legal point of view, the factual situation is clear. The investigation concludes that the Daimler Group has installed a large number of unauthorized defeat devices that clearly violate applicable law. Affected consumers are now obviously entitled to damages, after all, they have been sold a defective vehicle for which they paid the full purchase price. Legally, this can be considered fraud, committed not only against the environment but also against consumers. Mercedes drivers should check to determine if their diesel vehicle is affected.”

Responding to the claims, Daimler issued a statement, reading: “The outlined calibrations are known. In our view, these are not to be assessed as inadmissible defeat devices in the interaction and overall context of the highly complex emission control system.

“The vast majority of rulings in German regional courts and higher regional courts continue to be in Daimler’s favor: In approximately 95% of cases, the courts rule in favor of the company. At the regional court level, there are more than 15,500 decisions dismissing lawsuits in favor of the company; in only about 900 cases was the decision against the company. There are now around 900 decisions in our favor at the higher regional courts, and only three decisions against us.

“The German Federal Court of Justice (BGH) has also confirmed key points of Daimler AG’s legal opinion in several decisions. In particular, the BGH has held in these and other decisions that an allegedly inadmissible defeat device in the engine control unit alone does not give rise to a claim for damages.”

The German newspaper Süddeutsche Zeitung also reports that the KBA says the study has failed to produce evidence of previously unknown defeat devices at Mercedes-Benz. A KBA spokesman said: “The report shall designate eight defeat devices of the model concerned with the OM642 diesel engine. We are aware of these. They had already been examined and found to be ‘not inadmissible’.”

It added that since the Volkswagen Dieselgate scandal diesel, all vehicle models on the market from different manufacturers have been examined. The legally inadmissible defeat devices were named and treated in the context of recall campaigns. The vehicle model in question was initially part of a recall. However, software programming differs from other models in recall. “Therefore, there was no inadmissibility in this model,” it concluded.

— Paul Myles is a seasoned automotive journalist based in Europe. Follow him on Twitter @Paulmyles_