Currently reading: 'Several hundred thousand' UK cars affected by Mercedes emissions software tweak
Mercedes cars to account for most of affected models; brand says service action is to “strengthen confidence”
Sam Sheehan
3 mins read
19 July 2017

Daimler, parent company of Mercedes, is recalling more than three million of its cars in Europe to add software which will reduce emissions - a process the brand hopes will “strengthen confidence” for customers.

The brand, which has recently denied allegations in Germany that it has been cheating emission tests, said its service action provides customers with the option to have new software for cars running with the OM 607 turbocharged 1.5-litre four-cylinder diesel engine, which is used in Mercedes A-ClassB-Class, CLA and GLA models, to lower their output of nitrogen oxide.

Also affected are the engines codenamed OM 651 and OM 642 - the former being 2.0-litre and 2.2-litre diesel four-cylinder units, and the latter being Mercedes' 3.0-litre diesel V6. OM 651 is found in cars including the B-Class, C-Class and E-Class, while OM 642 is used in larger cars, such as the E-Class, S-Class and now GLE-badged M-Class.

The OM 607 engine was co-developed by Renault and is also used in some of its models, badged 1.5 dCi. Autocar is awaiting a response from the French brand to confirm the status of those cars, but it is used in the brand's B- and C-segment cars, such as the Clio, Captur, Mégane, Scenic and Kadjar. It's also used in the Nissan Juke, Micra and Qashqai as part of the Renault-Nissan alliance under the same name.

Nissan released the following statement: “Nissan is of course committed to upholding the law and meeting or exceeding regulations in every market where we operate. All our vehicles sold in Europe meet the Euro 5/6 emission standards. Nissan strongly supports New Real Driving Emissions standards, which will set a maximum level of pollutant emissions in real life conditions.”

This three million cars includes several hundred thousand cars in the UK, according to Autocar data, although an exact figure is still being ascertained by Mercedes-Benz UK. 

Comment: The truth about the diesel engine

Daimler said its process, due to cost about €220 million (£195m), is being “carried out in close cooperation with the German regulatory authorities” and allows engineers to add newer, more effective technology to the existing EU5 and EU6 engines. The process will take about one hour per car, with the first cars receiving updates in the coming weeks. The final cars are predicted to be completed late in 2018.

The latest emissions fix plan expands a process that has seen the issuing of new software for a quarter-of-a-million compact Mercedes models since March, of which 45% of affected cars have already received the change. The brand has also carried out a voluntary service action for the V-Class van, where 75% of customer vehicles have been worked on.

Opinion: Why diesel faces an uphill struggle for respectability

Daimler said it also plans to commence the "rapid" rollout of a new diesel engine family that will be more efficient and cleaner than the current range.

The brand's diesel technology was called into question last week when German transport ministry officials met with Daimler representatives, including head of technology development Ola Källenius, to discuss accusations that it has used software to improve the results of its diesel models in emissions tests.


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Daimler responded in an official statement, saying: "On the basis of our current information, we would fight any claim by the German Transport Safety Authority that we installed an illegal emissions control device with all legal means available."

Read more:

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18 July 2017

There must be a reason why the NOX levels are what they are. They surely can't be reduced with just a software change without detriment to one or more of performance, throttle response, economy or refinement. Otherwise, why were they not sold with lower levels in the first place? There has to be a catch. This doesn't seem like a good news story.

18 July 2017

If you want to lower NOx then you have to increase hydrocarbon output. The leaner you run an engine the more O2 you burn hence higher NOx.

21 July 2017

Diesels produce huge amounts of NOX due to much higher peak combustion temperatures. Spraying more Pantgher Piss - excuss me.....AdBlue - into the reducing catalyst will be the likely software change. The AdBlue tank is probably not big enough, and Daimler knows it, so folks are going to need to carry a few extra containers, because unless Daimler cheats again, I am pretty sure the cars can't be driven with an empty AdBlue tank. Anyone know the real story on this?


18 July 2017

That works out at 73 euro's a car for parts and Labour.

Bet Mercedes dealers can't wait to put the £130 an hour work to one side to do this fix. (I was being sarcastic) .

On a more serious note who in their right mind would submit their car for a fix after the VW diaster without knowing what is does and why it'll improve their car, oh and £200.

18 July 2017

Youre making the assumption (with zero evodence) that the Mercedes fix is the same as the VW one, we juet dont know yet, plus the VW one doesnt add "newer more effective technology". Best wait for the facts before commenting, really, after all asumptions make an ass out of u and me.


Of course this whole emisions thing could have been prevented if the EU ahd mandated NOx cats and DPFs 10 years ago.

19 July 2017

Are Mercedes saying that their cars are not peforming correctly? As far as i can tell, they are all doing fine. So, why have them messed with? I've not taken my VAG roup car to be "castrated", so why should Merc owners?


27 July 2017

There's a reason your VW is being called in. It's poisoning the air. Get it fixed.


18 July 2017

Another cheating company ?

So it's npt a recall ? silent recall then?

why wasn't this done from day 1 ?

surely the fix will affect economy, performance ?

so many questions, so little answers !!

18 July 2017

Is this 'emissions fix' going to reduce the lifespan of engine components?

Will it increase the rate of AdBlue additive consumption?

Will it increase vehicle running costs overall?

Why won't Daimler tell us?

18 July 2017

I note with interest that this is the 1.5 Renault engine.


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