Nox Sensors

[Rhino51]

I recently put my 2015 CLS in for a service and MOT. Both went fine with no MOT issues .
The service had the usual filters, oil change and Adblue topup.
The car was not used for the following few days as I was away on holiday. Then the first time I had it out on a few miles the engine light came on plus the message that Adblue required topup or the car would not restart after 500 mls. I took the car back to the garage where they carried out the diagnostics. They informed me that the nox sensors were faulty and to replace them
would be around £1200 . This would include new soft wear plus the sensors and labour.
Does anyone think this is excessive? The car has only done 23k.
Also I have heard there was a recall on this very subject .
Anyone shed any light ?

 

[Smart320]

Am sure that at that age and mileage as long as it was serviced only by MB dealer, I have read that MB is replacing them FOC. Try Googling or searching other threads on this forum, am sure other more knowledgeable members will advise you, do not rush off to spend £1200.

 

[CJD]

No recall as such, but the NoX sensors are a known problem - and can fail at any time - my went at about 48K, which they told me was quite late.
I had them replaced on my E350 FOC, when it had gone out of warranty as I had full MB history and the dealer was happy to do so.
The service manager told me they had done literally thousands of them.

 

[Rhino51]

I recently put my 2015 CLS in for a service and MOT. Both went fine with no MOT issues .
The service had the usual filters, oil change and Adblue topup.
The car was not used for the following few days as I was away on holiday. Then the first time I had it out on a few miles the engine light came on plus the message that Adblue required topup or the car would not restart after 500 mls. I took the car back to the garage where they carried out the diagnostics. They informed me that the nox sensors were faulty and to replace them
would be around £1200 . This would include new soft wear plus the sensors and labour.
Does anyone think this is excessive? The car has only done 23k.
Also I have heard there was a recall on this very subject .
Anyone shed any light ?

No recall as such, but the NoX sensors are a known problem - and can fail at any time - my went at about 48K, which they told me was quite late.
I had them replaced on my E350 FOC, when it had gone out of warranty as I had full MB history and the dealer was happy to do so.
The service manager told me they had done literally thousands of them.

Thanks for your reply.
I have already sent the details to MB and I’m awaiting a response.
This is obviously a regular problem with so many owners having the same Nox issues. My car has been serviced regularly by a MB approved garage so fingers crossed MB will help me out.
Cheers

 

[ioweddie]

My s205 c220d July 2015 is going in for the current diesel update which appears includes replacing the nox sensors...we shall see

 

[ioweddie]

Update done..no new nox sensors required...clean bill of health...car drives and performs exactly the same as it did before....

 

[C220DLondon]

Sorry - appreciate that this is a relatively old thread, but as I haven't yet had the update done on my C220D (and it being due to be done next week I am trying to get some info) have you noticed any negative affects on your car since this update was done? Are you using more AdBlue and does the gearbox seem different? Thanks in advance, Matthew

 

[Rhino51]

I had my CLS checked over my Mercedes registered garage
They reckoned both Nox sensors were faulty and needed replacing at a cost of approx £1200 .
So I tried down the recall and goodwill route, but to no avail.
MB suggested I get diagnostic check done by main dealer before any final decision was made.
Booked into main dealer and they replied quickly saying only one sensor was faulty and offered to replace it and diagnostics for approx £680 Jumped at it.
Got car back following day and has been going great with no warning lights . I also started using Shell V Power fuel. The Start , Stop which had stopped working is now functioning properly.