Nox sensor fault(5+visits to MB)

[Tezmufc]

Hi guys,

I have 2015 c220 AMG edition, recently had adblue fault with limited miles...

private garage wasted my time and £700 and couldn’t repair...

took to specialist MB to find a corroded wire which was £450 to repair, day later EML again so went back to find nox sensor had failed so paid up another £650 and was told no more problems.....

80 miles later EML so booked in again to find they reset it I think and cleared the fault (no cost).

80 miles again EML took back again to find the nox sensors needed an update from Germany to clear faults, cleared EML and was told this defiantly is fixed....

50 miles later EML so still calm booked back in at MB and explained this is a bit silly now so they kept for 3 days and completed 100mile trip in my car to make sure this would not return... found that the nox sensor they fitted was at fault and now the issue is resolved... no sorry or anything really... wasted ample time off work to take back and forward...

Now 3 weeks later the fault is back so booked in for next sat and was told the car is ok to drive but I feel the service provided is shocking and not even and apology, to top it off I was promised the diagnostics reports of all fault codes on my car and they still haven’t provided and not even a call back from the service/branch manager...

Any thoughts guys on what I should do and I have a written complaint ready but with the new addition EML I don’t know what I should do... this issue has put me off Mercedes and actually have a BMW ready to buy but this EML is going to loose me the car I want

 

[markjay]

Did the fault start after a service at the dealer involving a software update, by any chance...?

 

[Tezmufc]

No it all started when the wire went faulty so since then all I’ve had is problems and the main dealer can’t seem to fix it

 

[BlackC55]

Ad Blue issues.... They are a pain. Tricky to get right first time too.

We have had one car that has had a tank, injector, both NOX and software upadates to fix it.

 

[Uky]

It has been recognized that the placement of the sensors can result in problems: When a driver cold-starts the car and drives away, condensated water accumulates in the exhaust system before it is warmed up. Driving in an "active way" might cause the (cold) water at the bottom of the exhaust system drift towards the sensors. When it hits a sensor, the sensor breaks.

There is a workshop message, instructing to have a small hole drilled at the bottom of the exhaust system ( I think it was 3 mm) thus letting out the water and preventing it from breaking the sensors...

 

[Monkeylegend]

It has been recognized that the placement of the sensors can result in problems: When a driver cold-starts the car and drives away, condensated water accumulates in the exhaust system before it is warmed up. Driving in an "active way" might cause the (cold) water at the bottom of the exhaust system drift towards the sensors. When it hits a sensor, the sensor breaks.

There is a workshop message, instructing to have a small hole drilled at the bottom of the exhaust system ( I think it was 3 mm) thus letting out the water and preventing it from breaking the sensors...

Makes you smile. A car with so many sensors and complicated systems that even Mercedes struggle to fix and their solution is to drill a 3mm hole in the exhaust to drain the water out.

I wonder how many holes they will have to drill in the new all electric car when it is launched.

 

[Uky]

(A bit OT...) Given the fact that at least where I live, there is a desperate shortage of High-Voltage certified automechanics (A requirement for working with electric cars). Basically, the requirement/certification is all about knowing how to disconnect the battery modules and make safe such a vehicle before attempting repair of any sort, I have decided to stick with my 10+ years old combustion engine equipped E350CGI for now. Electric MB's are not without problems (as are most new technology products in the beginning) in spite of what the flashy commercials try to tell us.

 

[Sammerc350]

Hi guys,

I have 2015 c220 AMG edition, recently had adblue fault with limited miles...

private garage wasted my time and £700 and couldn’t repair...

took to specialist MB to find a corroded wire which was £450 to repair, day later EML again so went back to find nox sensor had failed so paid up another £650 and was told no more problems.....

80 miles later EML so booked in again to find they reset it I think and cleared the fault (no cost).

80 miles again EML took back again to find the nox sensors needed an update from Germany to clear faults, cleared EML and was told this defiantly is fixed....

50 miles later EML so still calm booked back in at MB and explained this is a bit silly now so they kept for 3 days and completed 100mile trip in my car to make sure this would not return... found that the nox sensor they fitted was at fault and now the issue is resolved... no sorry or anything really... wasted ample time off work to take back and forward...

Now 3 weeks later the fault is back so booked in for next sat and was told the car is ok to drive but I feel the service provided is shocking and not even and apology, to top it off I was promised the diagnostics reports of all fault codes on my car and they still haven’t provided and not even a call back from the service/branch manager...

Any thoughts guys on what I should do and I have a written complaint ready but with the new addition EML I don’t know what I should do... this issue has put me off Mercedes and actually have a BMW ready to buy but this EML is going to loose me the car I want

Sorry to hear your having problems, Yes unfortunately as you have found out like many, Mercedes stealerships are arrogant, unhelpful and for the most part wholly incompetent. Yes they will happily have you running around, losing wages and genuinely wasting your time, and because of there incompetence, however they won’t give it a seconds thought, that is if you allow them to behave like this.

My advice, arrange an immediate meeting with the Branch Manager, and demand he or she oversees your next appointment, make it clear you will be expecting a reduction in any invoices, and if this is not forthcoming you will proceed with legal action, make sure you record your meeting via Audio / Video, and state you would like your meeting followed up with a letter laying out what was agreed at your meeting, don‘t take just there word a smile and a goodbye hand shake, otherwise you will be in for a surprise when you receive your follow up letter which 9 times out of ten will not be confirming what you agreed.

My last bit of advice, ensure you do record your meeting as it’s your only proof what you said and what if anything they (Mercedes) agree they will do and honour

Good Luck!

 

[dmb007]

Just to balance things I have had 4 sensors replaced (on a 2015 Petrol E400) and my wife 1 sensor replaced (2015 C220 Diesel).

All FOC at the main dealers. With a courtesy car.

It took 2 dealers to sort. First one (where I bought car from) thought only 2 sensors on E400. The first dealer has since closed down.

Regards
David

 

[tombell]

Hi guys,

I have 2015 c220 AMG edition, recently had adblue fault with limited miles...

private garage wasted my time and £700 and couldn’t repair...

took to specialist MB to find a corroded wire which was £450 to repair, day later EML again so went back to find nox sensor had failed so paid up another £650 and was told no more problems.....

80 miles later EML so booked in again to find they reset it I think and cleared the fault (no cost).

80 miles again EML took back again to find the nox sensors needed an update from Germany to clear faults, cleared EML and was told this defiantly is fixed....

50 miles later EML so still calm booked back in at MB and explained this is a bit silly now so they kept for 3 days and completed 100mile trip in my car to make sure this would not return... found that the nox sensor they fitted was at fault and now the issue is resolved... no sorry or anything really... wasted ample time off work to take back and forward...

Now 3 weeks later the fault is back so booked in for next sat and was told the car is ok to drive but I feel the service provided is shocking and not even and apology, to top it off I was promised the diagnostics reports of all fault codes on my car and they still haven’t provided and not even a call back from the service/branch manager...

Any thoughts guys on what I should do and I have a written complaint ready but with the new addition EML I don’t know what I should do... this issue has put me off Mercedes and actually have a BMW ready to buy but this EML is going to loose me the car I want

Bought a 62 Plate Merc ML at the beginning of May. A week ago I got message something like "1,700 miles before AdBlue runs out". I filled AdBlue to the brim. EML light still on. Tried all the tricks on the web to turn it off. No Go. Next day "600 miles engine won't restart". Took it to MB Oxford today. They are getting 2 Nox sensors for the end of the week. They want £1,871.52. and will have to remove exhaust. 3.8 hours

 

[tombell]

Bought a 62 Plate Merc ML at the beginning of May. A week ago I got message something like "1,700 miles before AdBlue runs out". I filled AdBlue to the brim. EML light still on. Tried all the tricks on the web to turn it off. No Go. Next day "600 miles engine won't restart". Took it to MB Oxford today. They are getting 2 Nox sensors for the end of the week. They want £1,871.52. and will have to remove exhaust. 3.8 hours

 

[Deleted member 65149]

I have had both NOx sensors replaced twice on my 2012 M276 (C350 petrol). The first time was shortly before the 3-year new car warranty ran out so no hassle.

The second time they were replaced was about 21 months ago when the car was 7 years old but only done just over 30k miles. Following a lot of discussion with MB UK, they finally agreed to contribute £1000 to the repair cost.

Last week the EML came on again with a code of P2214. I reset it but it came up again within a couple of days. I tried another reset followed by “an Italian tune up”; 20 or so miles later and up popped the EML again, with the same code.

The car is booked in for a service and MoT with the same dealer I bought the car from new and had all work done on it. I can’t decide whether or not to pay their exorbitant fee just to tell me what I already know which is basically that things aren’t looking good and a NOx sensor may fail soon. Or would it be better to wait until the sensor fails and raises the appropriate code, then get it replaced under the 2 year parts warranty?

The more reports on the NOx sensors that appear on this forum, the more it seems that Mercedes are struggling with this issue and have yet to solve it.

 

[tombell]

Bought a 62 Plate Merc ML at the beginning of May. A week ago I got message something like "1,700 miles before AdBlue runs out". I filled AdBlue to the brim. EML light still on. Tried all the tricks on the web to turn it off. No Go. Next day "600 miles engine won't restart". Took it to MB Oxford today. They are getting 2 Nox sensors for the end of the week. They want £1,871.52. and will have to remove exhaust. 3.8 hours
Does anyone have the part numbers for the nox sensors and the adblue tank

 

[tombell]

Mercedes Quote with Part Numbers for replacing Nox Sensors on 2012 ML250 TOTAL £ 1,620.96

Labour 3.8 HOURS £385.70

MA166 520 02 23 NOISE CAPSULE £ 88.50

MA000 905 35 03 104A05 NOX SENSOR £417.00

MA202 490 08 41 108C05 CLAMP £ 10.00

MA000 492 08 81 101D04C SEAL RING £ 5.75

MA000 492 08 81 101D04C SEAL RING £ 5.75

MA202 490 08 41 108C05 CLAMP £ 10.00

MN910143 008 006 102D06C HEXALOBULAR BOL £ 1.40

MN910143 008 006 102D06C HEXALOBULAR BOL £ 1.40

MA000 905 36 03 104A13 NOX SENSOR £379.00

MA002 995 49 02 107E09 PIPECLAMP F EXH £ 46.30

NET £1,350.80
VAT £ 270.16
TOTAL £ 1,620.96