The software programs allegedly used by Mercedes-Benz could be similar to those developed by Volkswagen
19 February 2018

Mercedes-Benz has equipped various diesel models with software that may have helped them pass emission tests, according to a report published by German newspaper Bild am Sonntag.  

The report, citing information Bild am Sonntag says is contained in a US Department of Justice investigation, claims engineers from Mercedes-Benz parent company Daimler developed various software programs that allowed unspecified diesel models to pass US emission tests through the manipulation of the engine and its selective catalytic reduction filter.

Volkswagen engineer sentenced to prison for Dieselgate involvement 

The software programs are alleged to have been tailored to the specific demands of various cycles in the US emission testing procedure, allowing the diesel engine of Mercedes-Benz models to run in an ultra-clean state, but only for limited periods of time, after which it was then switched to a so-called “dirty mode”.

The manipulation software programs allegedly used by Mercedes-Benz to allow its diesel models to pass the US tests could be similar to those developed by Volkswagen and threaten to drag it further into the Dieselgate scandal.

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According to the information obtained by Bild am Sonntag, included among the software programs alleged to have been developed for diesel-powered Mercedes-Benz models is the “Bit 13” function. It sees the diesel engine switch to “dirty mode” once it emits 16 grams of NOx. This corresponds, it says, to the duration of the US highway test cycle.

Also suspected of being used is the “Bit 14” software function. It switches the engine to “dirty mode” under certain temperatures and preset periods of time. This function is allegedly particularly suited to allowing cars to pass the FTP-75 warm test cycle.

Bosch created Volkswagen Dieselgate cheat software, study alleges

Another software function called “Bit 15” is claimed to have been used during the US06 test cycle. It is programmed to switch off the SCR exhaust gas after-treatment system after 16 miles.

Bild says US investigators have also uncovered a further suspicious software function within the control system of various Mercedes-Benz models. Called Slipguard, it reportedly detects when the car is being tested on a rolling road and is claimed to influence the dosage of urea-based AdBlue solution within the SCR exhaust gas after-treatment system.

The allegations come after news that the German ministry of transport is set to demand Mercedes-Benz issues a recall for diesel-engined versions of its Vito commercial van due to discrepancies.

According to sources, tests carried out on the Vito reveal its SCR filter is programmed to reduce the injection of AdBlue to allow it to be filled during service intervals - thus reducing its efficiency and leading to higher NOx values than those claimed by Mercedes-Benz.

Mercedes-Benz is not commenting on the allegations of diesel emission manipulation.

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Comments
10

19 February 2018

Sigh... another supposed premium marque caught up in the scandal. 

I suppose a bit like VAG this is what happens when trying to equip older generation Diesel engines with new emissions software rather than design a new engine from the ground up.

The ancient 2.1 OM engine can often be seen in older Merc’s spewing soot out out much like the VAG 2.0tdi pre CR development 

19 February 2018

Good old premium technology from the Germans LMFAO. Serves the owners right for buying cars based on their badge. That history of good old reliability left Germany a few decades ago but for some people it's all about living in the past. 

19 February 2018

Would be a good title for a film. The funny thing is there's computer programmers out there on £35k a year who know the truth and could spill the beans and leak the code at any time.

I suppose nothing's been proved YET but it leaves a bad taste (no pun intended)

typos1 - Just can’t respect opinion

19 February 2018

Here we go again, another scanda from another German car company. And yet the UK buying publci will still continue to buy Germam cars in their droves while the motoring press will continue to test their cars, advertise them etc. If poor reliability and over-hyped engineering prowess isn't a reason not to stop buying these cars, what is? Clearly manipulating emissions and using animals during tests isn't. It's time to stop buying average and unreliable cars from these companies which have no ethics, morales and who cheat.

19 February 2018
Roadster wrote:

Here we go again, another scanda from another German car company. And yet the UK buying publci will still continue to buy Germam cars in their droves while the motoring press will continue to test their cars, advertise them etc. If poor reliability and over-hyped engineering prowess isn't a reason not to stop buying these cars, what is? Clearly manipulating emissions and using animals during tests isn't. It's time to stop buying average and unreliable cars from these companies which have no ethics, morales and who cheat.

.  might not just be a European ( see what I did there?) might be a global thing?

Peter Cavellini.

19 February 2018

I am convinced Mercedes would not be this loose and naive as to practice such deeds in the light of the BMW and VW sagas..

Maybe it's their rivals still smarting from the heavy fines and loss of market share are trying to muddy the water for the Daimler group... 

Don't believe they did... 

19 February 2018

you must be looking at this with your Mercedes goggles on. If anything, I’m expecting to see bmw to be dragged in soon.

20 February 2018
Reading the comments section, there always seems to a be an unhealthy amount of xenophobia present in the responses.

IF the latest emissions allegations prove to be true then obviously there should be consequences for Daimler and ditto for BMW (if evidence comes to light that they have cheated as well) but that's yet to be proven and would in any case reflect the actions of a business and NOT the German people.

I'm proud to be British but Britain has a chequered history of abusing our position of power, so perhaps it would be a good idea not to start bashing other countries and focus instead on the misdeeds of the businesses and not where they are based.

20 February 2018
MarkII wrote:

Reading the comments section, there always seems to a be an unhealthy amount of xenophobia present in the responses. IF the latest emissions allegations prove to be true then obviously there should be consequences for Daimler and ditto for BMW (if evidence comes to light that they have cheated as well) but that's yet to be proven and would in any case reflect the actions of a business and NOT the German people. I'm proud to be British but Britain has a chequered history of abusing our position of power, so perhaps it would be a good idea not to start bashing other countries and focus instead on the misdeeds of the businesses and not where they are based.

Well said, it is the business practices. Even though MB and BMWs aren't proven yet , according to "dirty diesels" program on Netflix , the estate cars tested from both companies  emit 6 times more than what they quoted. So eventually they will be pulled in. Renaults and Fiats will follow as well. 

I think it is the governing body/countries bringing in unacheivable( economically) targets which has caused this issue all throughout Europe. Don't know if JLR has done it too. Lets assume they haven't  and hey for all those who moan about the price they charge, this could be the reason. 

If you don't look back at your car after you parked it, you own the wrong car.

20 February 2018
MarkII wrote:

Reading the comments section, there always seems to a be an unhealthy amount of xenophobia present in the responses. IF the latest emissions allegations prove to be true then obviously there should be consequences for Daimler and ditto for BMW (if evidence comes to light that they have cheated as well) but that's yet to be proven and would in any case reflect the actions of a business and NOT the German people. I'm proud to be British but Britain has a chequered history of abusing our position of power, so perhaps it would be a good idea not to start bashing other countries and focus instead on the misdeeds of the businesses and not where they are based.

Rightly so as people buy their junk apparently because of their engineering and intergtrity, Both of which have been destroyed by Volkwagen and soon to include Daimler. The only people that would be upset are people who've been made a mug of that fell for their lies and buy into their cars. It must be embarrassing being BMW right now

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