NOX Sensor Fault - Goodwill Gesture?

Matty K

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Hi All, I’m sure this issue has been discussed plenty of times but I’d appreciate anyone and everyone’s feedback.

I drive a 2017 C220D Coupe that has only clocked up around 15300 miles. I bought the car from a private garage and not a Merc dealership so therefore is no Merc warranty etc on it. The Orange Engine Maintenance/Warning light flashed up last week. I booked it in at my local Halfords who ran a diagnostic on it and found that the sensor had been knocked, the NOx sensor and it needed to be replaced. I then phoned my local Merc dealership who said they can book me in for a diagnostic for £168inc VAT to determine what the problem is and potentially could replace it as their ‘goodwill’ procedure. It’s the first time I’ve heard of this Goodwill practice that they offer. Does anyone know what determines whether my car/the problem qualifies as part of their goodwill? I’m not sure whether to go ahead with this only for them to turn around to me and say that they aren’t going to offer the goodwill and I will have therefore paid £168 for something that I already knew. Is it worth biting the bullet and trying it considering that I didn’t get the car from a Merc dealership but because the car isn’t very old and got relatively low mileage? Or would I be best off putting the money towards getting it repaired/replaced at another approved garage? Thanks everyone
 

ajlsl600

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Is ALL the servicing up to date and exactly as speced by benz, do you have evidence of this? If u do ,maybe if not,I doubt.
Get something in writing. from service manager stating terms for goodwill,
Frankly "goodwill" on a crxp sensor isa bit of a joke,by rights nox sensors and some should be a recall.
Wish u luck.
 

Botus

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Mercedes are under orders to rectify illegal vehicles under the dieselgate scam that affected LOTS of manufacturers.

It could be the dealer is

1) not very busy and looking for work
2) a decent one wanting to meet Mercedes obligations and flash the updated ECU software they have to install on their cars to get out of trouble and help out a customer
3) received new info about their reputation taking a kicking with NOX sensor failure and dieselgate fun, and Merc UK have thrown a few crumbs at dealers to help make it happen
4) the receptionist is confused and just following a list of what to say

these days merc want to understand how their cars are going by pulling info from your car on how its been maintained (service records or not in the cars memory) and how its running / what's failing (diagnostic info its stored for their own development / understanding). And to find a new customer with a fairly new car that might like to pay their big labour rates etc. or better still lease a brand new one

Warranty might still be valid.... JUST, a missed service on the engine doesn't allow a faulty radio to go unrepaired... But it will leave you in a difficult place re the Engine sensor... But there is such a thing as good will, when a nice car (usually with a full dealer history) has a fault so close to the end of its warranty. They can consider helping pay for the fix. What that "help" looks like is totally open-ended. But dieselgate will tend to get you in a better place than you would have been as they've been naughty and got caught.

Additionally modern cars are FULL of quite interesting software everywhere, its not just the engine.... often it need to be replaced with better stuff... Halfords can't do that - and few other garages outside a main dealer can apply these updates. There's a few and they could be cheaper... but often hard to locate, busy and with less time to sort out the mess when the car has a hissy fit for no good reason.
 
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ajlsl600

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Read up on issues, and there are a few, that come up as a result of any update, my information, understands is that, everything gets updated like it or not. My advise, have service manager get in car and confirm what if any other issues you have Before agreeing to the work. Update. So there can be no questions in the event of any issues when you get the car back.
 
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Matty K

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Thanks for your feedback guys. After reading through a few threads, it seems to be quite a common issue. Should this really be happening to a car that is only 3yr old with 15k miles on the clock. Seems to be too much of a common issue on cars that aren’t very old/don’t have too many miles on. I appreciate that these sensors may have a ‘shelf life’ but surely Merc should be doing something to rectify an issue that seems so common. I think I am going to bite the bullet and take it to my local Merc dealership and potentially pay the £168 diagnostic fee and pray that they may do it as a goodwill gesture.
 

Botus

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yes, 3 interesting bits of coding inside the engine computer present different issues and all need to be removed - but many too hung up that there could never be anything wrong, they like to debate or shout down others.

On top of that the NOx sensor (a bit in the exhaust sniffing fumes) was built too cheap and they have just been problematic.... its likely yours just failed

Which as Merc know, but don't like to talk about - is because the original sensor was never fit for purpose and thus should all be sorted at their cost... this is all VERY normal on all brands and has been for 35 years. But the better they keep a lid on it, the less their reputation gets a kick and even more important they can mug off customers and make them pay…. EU rules battled this stuff years back and the UK reluctantly updated consumer law in 2015, with a pretend attempt to help. But the shops / manu just say go away and it works 99% of the time

There have been a number of replacement parts for the NOx sensor and a number of later software attempts trying to find a cheap fix. None worked. Now the correct longer term resolution is to swap to a better designed part that can't work on older car's software.... so now you need 3 software updates for the engine....

assuming yours has adblue….
a part ref update (to show the need for the new design NOx sensor)
an SCR update and reset (part of the adblu system)
the last and best ECU update which suits the sensor and gets your emission meeting its homologation rules for real (rather the pretend effort its got at present)

a side effect of having it right, the DPF might last a lot longer, as that too should run through a re-gen cycle correctly (which isn't the case on most Merc tractors - as that bit of software and sensors were all rather "interesting" too)

Note: the car may drive a bit funny for 50 miles after the update at it settles (adapts back to normal) - all to be expected, with gear change points, the way its running, fuel and adblue consumption may appear higher (and indeed MIGHT be slightly higher, its a possible side effect of making it legal - or more likely the re-gen working for the first time in its life....)

If it were my car I'd bite the bullet go informed to a main dealer and expect them to pay for the engine sensors.... then if its got comand, grovel for a cheap Map update and any Radio / hifi updates that it should have. (Comand, got free maps inside first three years, the cheaper system you always paid - they used to do deals for 99 quid)

If you got a basic service try and haggle the diagnostic cost within the price.... they'd feel happier to help sort the engine without robbing you, and after all the updates you'd have a more valuable, better secondhand car with a service history...

then you can walk away from main dealerships forever and get the next service and gearbox oil change done at an indepenant, knowing you shouldn't need any software fixes again.

take a video of the dash lights before and after.... and if you hand over ANY money and a warning light is still on when you pay don't accept the keys back !!!

diagnostics is a scam its 30 mins work max and the kit is sitting there doing nothing and they have to plug in to update anything and or do a service

did you check it there's a recall for the emissions ? https://www.gov.uk/check-vehicle-recall never worked for me but may as well look....
 
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malcolm E53 AMG

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Thanks for your feedback guys. After reading through a few threads, it seems to be quite a common issue. Should this really be happening to a car that is only 3yr old with 15k miles on the clock. Seems to be too much of a common issue on cars that aren’t very old/don’t have too many miles on. I appreciate that these sensors may have a ‘shelf life’ but surely Merc should be doing something to rectify an issue that seems so common. I think I am going to bite the bullet and take it to my local Merc dealership and potentially pay the £168 diagnostic fee and pray that they may do it as a goodwill gesture.

Yes, with a 17 plate car that’s exactly the thing to do citing not fit for purpose with a car on 15k miles and three years old
 

CJD

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It all depends upon your local MB dealer.
I had them replaced FOC on my e350 at 4 years old.
It did have full MB history though -
the dealership told me they personally replace them all FOC if the car has full service history.
 
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Matty K

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Checked the link, it appears that there was a outstanding recall found. Went on to MB website and entered my VIN and my car has been affected with the Diesel Software Update. Definitely a talking point to bring up with them. Thanks for the info, much appreciated
 
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