EML Light on, VCDS scan implies an SCR fault?

[mmi]

Happy New Year to All!
I managed to sent sensor across channel and unit is replaced. Now, after ECU scan alarm Nox sensor disappear, unfortunately message on the dash board still display 250miles . I try to utilise VDCS version 22.10 to reset , but I can't find this function(there films on you tube, but I can't see long adaptation window). I wonder if you can help me.

Below are some information reordered for future
Chassis Type: 7H-VN75 (7E0)
Part No SW: 04L 906 056 KL HW: 04L 907 445
Component: R4 2.0l TDI H02 6166
01-Engine -- Status: OK 0000

IDE03142 Remaining vehicle distance until reducing agent deficiency 6143.140 km
IDE04098 NOx-sensor NOx11:65535 ppm / NOx21:---
IDE10241 Reducing agent pump module relative press.: calculated 6148 mbar
IDE10247 Reducing agent tank volume: act. value calculated 14.169 l
IDE10248 Reducing agent supply pump: offset factor calculated 0.984
IDE10249 Reducing agent fill level sensor: act. value 106 mm
IDE10250 Reducing agent return pump: adapted displacement 0.038 ml
IDE10251 Reducing agent supply pump: measured resistance 4.121 Ohm
IDE10579-MAS01493 Reducing agent system pressurization release conditions-Engine running Condition met
IDE10579-MAS10831 Reducing agent system pressurization release conditions-Heat. strategy: enable Condition met
IDE11220 Reducing agent system: current status COSCR_pressure control
IDE11221 Reducing agent system: last status COSCR_no pressure control

Please post

1) blockmap of module 01-Engine
2) blockmap of module 17-Instruments
3) full VCDS Auto-Scan
4) earlier VCDS Auto-Scan where the NOx sensor fault was

How-to (see picture below):
VCDS > Applications > Controller Channel Map >

Single Controller Address 01 > Go​

Single Controller Address 17 > Go​

Other selections as below:​

Tick - Measuring values,​

Select - CSV file​

​

​

The files blockmap-01... and blockmap-17... will be in folder C:\Ross-Tech\VCDS\Logs\....​

 

[Ares B]

Hi MMI
Thank you very much for fast response, really appreciate
Attached files

 

[mmi]

Hi MMI
Thank you very much for fast response, really appreciate
Attached files

Thanks. Interesting...

Could you please make a fresh VCDS Auto-Scan as in the posted scan VCDS could not communicate with Instruments. Just to confirm the communications between controllers are working.

I believe the following data extracts in red/yellow are the indicators of the mystery:


Engine detects AdBlue level correctly (106 mm) and range based on that is ok - 6143 km.
However, between Engine and Instruments there is quite a discrepancy 6143 km vs. 250 km. Also warning level is set in Instruments.

My guess is that the engine thinks the AdBlue is not as effective as it should be - thus "SCR inducem system status-incorrect reagent" is set to "INCORR_REAG"

Question: has the DPF been cleaned or replaced recently - because DPF ash mass counter (IDE06059) has been recently cleared??

---

There are some similarities with @Keith 81 's challenges here:

Adblue /software version

Evening all still having issues with my t6 had egr replaced yesterday still have the adblue error with MFD countdown would anybody know what the most up to date software is for my vehicle mine is ver 6163 I think

www.t6forum.com

 

[Ares B]

Hi MMI
Thank you for your time to review attached data
I will scan again system earliest on Wednesday evening when back home ( I need to travel from work for few days).
Is any chance that ad-blue quality is not correct?
I need to admit that I try to perform test SCR , where you are instructed to keep brake and accelerator lever down. Result from this test was Abandoned- safety reason, or similar

Question: has the DPF been cleaned or replaced recently - because DPF ash mass counter (IDE06059) has been recently cleared??
I believe this was desperate step when I play with VCDS.

 

[Jonwm]

Not sure if relevant to this but as I mentioned in a an earlier post I get frequent P20EE fault and mines on original 2016 software, adblue last ages, it went to VW in November and they said it didn't need any software updates.

Today I've received an email from VW Dealer regarding a technical recall on my chassis number, I asked what it was and its a software update, seems strange its come up after 6 years but wandered if anyone else with this fault has had the message today?

I'll lose my map but hopefully will cure the P20EE, I just leave it on now I don't even clear the fault.

 

[Ares B]

Hi MMI
I back to home tonight. Please find attached files for block 17 /instruments - engine stopped & engine running.
I will travel tomorrow again , but I will keep eye on posts
Thank you again for your effort

 

[mmi]

Hi MMI
I back to home tonight. Please find attached files for block 17 /instruments - engine stopped & engine running.
I will travel tomorrow again , but I will keep eye on posts
Thank you again for your effort

Thanks for the files - still the same

When you've got time please post a fresh VCDS Auto-Scan. Also please post a picture of your dash AdBlue display (with remaining range).

Is any chance that ad-blue quality is not correct?

That certainly would be a possibility - and would be an inexpensive repair. Certainly could measure the quality of the AdBlue

adblue refractometer - Google Search

or just simply drain and replace with some fresh.

Another suspect is a real fault somewhere in the chain of NOx-reduction system, either in AdBlue injection or in the NOx catalytic converter's (NOx trap) performance itself - your van has done almost 250.000 km's thus not totally impossible either of them failing. Life expectancy of the DPF (where NOX trap resides) is approx. 300.000 kms.

If you would like to sacrifice some of the remaining range you could measure the actual NOx levels as described below (post #20)

Adblue /software version

Evening all still having issues with my t6 had egr replaced yesterday still have the adblue error with MFD countdown would anybody know what the most up to date software is for my vehicle mine is ver 6163 I think

www.t6forum.com

 

[Ares B]

Hi MMI
Thank you for your prompt response
I understand that van indicate high mileage and potentially issue with DPF can appear very soon. I try to be optimistic and keep happy with my conversion!

I will check all ID mentioned above when I come back home (please be patient, currently around a week )
I will do also photograph of the dashboard, I forgot to make photograph when I back home last time. I can assure you still shown adblue and spanner with 250 miles :-(

Thank you again

 

[mmi]

Just another oddity in the logfile blockmap-01-04L-906-056-KL (engine running) (post #62)

​

I have never logged anything in IDE09648, -49, -50. Checked quite a few logs (more than 10 hours of engine running)
Only found "activity" on last line - marginally increased NOx emission.

 

[Ares B]

Hi MMI
Thank you for your patience. I back home today and hopefully I will not need to travel soon.
I need to admit that this van was purchased on auction and I don't know previous owner and history
Please find attached auto scans when engine not running and running and photograph of the dash board .
Please note by mistake I switch- on transport mode when I scan last time
Thank you
Arek

 

[Ares B]

Hi MMI
Today was done another step forward, complete adblue tank was replaced with another second hand unit and there is some improvement. New information's are display on the dashboard. Attached are two photographs one after and one before. Unfortunately range is reduced from 250 to 200 miles .
What else can I do?


after

before

 

[mmi]

Hi MMI
Today was done another step forward, complete adblue tank was replaced with another second hand unit and there is some improvement. New information's are display on the dashboard. Attached are two photographs one after and one before. Unfortunately range is reduced from 250 to 200 miles .
What else can I do?

View attachment 185905
after
View attachment 185906
before

Thanks for the scans and the pictures. It's interesting that the dash reports an error but there's no fault code in the log.

Can you make a VCDS-log as proposed before (post 67) and below:
Post in thread 'Adblue /software version'

Adblue /software version

Evening all still having issues with my t6 had egr replaced yesterday still have the adblue error with MFD countdown would anybody know what the most up to date software is for my vehicle mine is ver 6163 I think

www.t6forum.com

 

[Ares B]

Hi MMI
I scan yesterday block 17 ( file attached). I was look also at electric diagram for T6(attached with circuits), where I found a connector 17p which is related to can bus communication. I made one more test of the block 17 with connector disconnected. I was surprised because all measurement was exactly the same! I never deal with electric on the car, but my suspicious is that fault also can be:
1- wiring between equipment
2- unit J623
From your experience is this is possible? Do you have any drawings/layouts with location of equipment?

 

[mmi]

Hi MMI
I scan yesterday block 17 ( file attached). I was look also at electric diagram for T6(attached with circuits), where I found a connector 17p which is related to can bus communication. I made one more test of the block 17 with connector disconnected. I was surprised because all measurement was exactly the same! I never deal with electric on the car, but my suspicious is that fault also can be:
1- wiring between equipment
2- unit J623
From your experience is this is possible? Do you have any drawings/layouts with location of equipment?

Well, the VCDS Auto-scans from Monday have no related faults thus there shouldn't be any related wiring issues. However, not every circuit is not confirmed at engine startup. For example, I believe, the NOx sensor circuit which you disconnected is operated later when engine is running at normal operating temperature - typically 10-15 minutes after setting off. This NOx sensor behaviour was measured e.g. here:

[T6_measured] NOx emissions, AdBlue consumption, DPF regeneration - Before and after ECU update

Introduction An update campaign for T6 EU6 diesel engines took place in 2019-20. Affected engines were on van of model years MY16-MY18, including some of MY19. For M1 class (passenger carriers, VIN WV2...) the update was an official recall. For N1 class (VIN WV1....) the update was not...

www.t6forum.com

Also the disconnected connector T17p is between NOx sensor and engine (J623) thus it would take a while a fault would propagate to the controller 17-instruments. Have you checked engine fault log after disconnecting the T17p?

Do you have any drawings/layouts with location of equipment?

The actual locations and repair/replace instructions are in Workshop manual for the engine.

 

[johnnywilkins]

Not sure if relevant to this but as I mentioned in a an earlier post I get frequent P20EE fault and mines on original 2016 software, adblue last ages, it went to VW in November and they said it didn't need any software updates.

Today I've received an email from VW Dealer regarding a technical recall on my chassis number, I asked what it was and its a software update, seems strange its come up after 6 years but wandered if anyone else with this fault has had the message today?

I'll lose my map but hopefully will cure the P20EE, I just leave it on now I don't even clear the fault.

Hello mate, could you tell me which model you have please as i have the same problems with my van.

 

[Jonwm]

Hello mate, could you tell me which model you have please as i have the same problems with my van.

Hi mate
Mines a late 2016 150 DSG, it's going in again in 2 weeks for a technical update so will let you know if that fixes it.

What years yours?

 

[johnnywilkins]

Mines a 68 plate 150 kombi, it's in tomorrow, I've told them to clean the Adblue nozzle out, cos apparently they can get blocked with crystallised Adblue, then do the 6166 software update . Cheers mate, I'll post the result on here.

 

[Ares B]

Hi MMI
I take one day holiday from work to look at ad-blue saga again. I decided to take van for short trip to activate the SCR unit, to be able to see what is happened after SCR unit switch on and to record values from post 'Adblue /software version'. I was more 'confused .com' all values were active and changed during driving etc.
Then was a miracle after driving around 10 minutes was a beep and.....

My plan was to insert a recorded values for reference, but I can't see the file in the log folder?
From one side I am very happy that issue is resolved, but from another side I am disappointed that I don't know if the issue was with sensor only or some where in the tank for ad-blue.
I can say only: WV should advise people take a van for run after repair of the ad-blue system

I would like to say thank you very much to MMI for all time and effort with my case !!!

 

[mmi]

My plan was to insert a recorded values for reference, but I can't see the file in the log folder?

Perhaps simply missed to start logging by clicking Log-button?

Anyways, glad to hear the issue was resolved - hopefully for good.

 

[Brew]

Hi All,
I thought I'd let you know my experiences.
I have a 18 Plate 150 DSG Kombi purchased at 6 months old and has now done 35000 miles. I first had the engine warning light come on a week after the third year service (convenient eh) I took it back and it was reset.
Thereafter I have had the alarm come up 4 times, I have a AutoLink AlL319 OBD reader and the fault has always been P20EE, which I have reset. I have always kept the adBlue tank topped up and the van seems to use it at a constant rate. I have no idea what software the van is running. I use V power diesel were I can and shell or pump adBlue.
But, here is the thing, the engine light has only come on during very long runs when the engine is well up to temperature and ONLY when using cruise control. I don't use cruise control all the time, particularly if the traffic is heavy, today I had completed about 150 miles of fast A road and motorway and when I activated cruise control on the A1 the engine light came on within 10 miles. Read the fault code when I got home, P20EE, so reset it.
Almost at the point of carrying the fault reader with me on long journeys just to get rid of the yellow light glaring at me!