AdBlue Countdown: No Error Messages

Hello everyone,

Please excuse us if this topic has already been discussed. We have read the relevant threads, but have not found a solution to our problem. Furthermore, we are facing a time-sensitive issue.

We are in Mongolia with our VW T6, model year 2016, and we have a "Ad Blue (DEF) countdown" warning (engine will not start after 1000km). We need to be at the Chinese border on September 1st, so we would be very grateful for your help.

We had the error codes P204F and P20EE, along with a countdown timer related to AdBlue. We were able to clear these errors using a simple OBD scanner and the CarScanner app, and they haven't reappeared.

We have to mention that we already experienced the countdown, including error messages, approximately 8,000 km ago. However, these issues disappeared after a longer period of consistent driving.

- The DPF regeneration is functioning correctly.
- AdBlue is filled (70%) - we can't say much about the quality - it may not be perfect (it comes from Kazakhstan and a little from Mongolia, and we had it filled by a workshop after the problem occurred).
- We removed and cleaned the AdBlue injector. It was slightly dirty.

We have a VCDS here since today, and we have already done the following:

- Autoscan performed.
- AGR check passed - OK.
- IDE00471: DPF regeneration service performed and completed.

We wanted to test the efficiency of the SCR, but it's not triggering, and the incandescent lamp isn't lighting up. What could be the reason for this?

We performed the auto-scan and have attached the results.

Maybe you have some more ideas about what we can do. We're feeling quite desperate right now.

Thank you in advance, and best regards.

Dominik.

Hello,

Are the temperature readings for the DPF plausible? Is the DPF regeneration function working?

The NOx sensor might also be faulty. Is the ECU software up to date?

Best regards, Rainer.

Hi,
I've noticed that at a mileage of 154,171 (approximately 130 km before the recording), errors are stored in four control units, with some of the date entries being nonsensical. Three of these relate to communication problems between the control units. Consequently, the main control unit (MSG) is not reporting "ready." This indicates a wiring problem.
It may not be related to the AdBlue issue, but it could be.
First, check the connection between the generator and the vehicle's electrical system.
Regarding error codes P204F and P20EE, one can find quite a bit of information on the internet, including https://autodiagnostic-richter.help/fehlercode-p20ee-p204f..
And most importantly, make sure to completely fill the AdBlue tank, otherwise the counter won't reset.
hg
Herbert.

Hello Dominik,

Have you read this post and looked at the measurements?

https://community.dieselschrauber.org/en/viewtopic.php?t=31284&highlight=adblue

Best regards,

Michael.

Hello everyone,

Thank you very much for your input and support!

Unfortunately, the situation had become so complicated that we had to take action. Our visas are about to expire, and unfortunately, obtaining spare parts here in Mongolia is extremely difficult, if not impossible.

Therefore, we have temporarily "forgotten" to refill the AdBlue. This allows us to continue our journey for now, and we will take a closer look at the issue when we are back in Europe.

One thing I was able to confirm recently: the second NOx sensor is working and receiving power. In contrast, the first NOx sensor, located before the SCR catalyst, has 0V. The error related to the Body Control Unit is now resolved.
The regeneration process is continuing smoothly.

We will definitely take a closer look at that again later.

Thank you all again for the tips and the help!

Quote:

Therefore, we have temporarily "forgotten" to add AdBlue to the car.

This allows us to continue our journey for now... }
How would one achieve that in Mongolia? Tuners are probably scarce there.
Herbert.