Adblue Refill Issue - not resetting after refill

[Mickey43]

My adblue warning light had been on for a few days so I filled up today - the warning said approx 900 miles left.

 

I put 5 litres in, switched on the ignition for 30 seconds then started up.  Warning went away and the adblue range went to 4000 miles.  All good, set off on a drive.

 

About an hour in, the sensor warning pinged again, saying there was 650 miles left.

 

Went and bought another 5 litres to try and reset it -  it all went in, so 10 litres in total today.    Started up, same procedure but the warning is still there.  650 miles left    Drove home, turned off and restarted a few times but it wont go away.

 

Sounds like a sensor issue or something - any ideas or anyone else had this??  

 

Car is a 16 plate L&K 190 tdi

 

cheers

 

[Mickey43]

Also - the message says

 

Error: AdBlue (DEF). No engine start in 650m

 

I dont think it usually says "error" in a normal refill warning.

[Guest]

I think you need to add at least 10 litre before it registers.

[Jonatan]

Hi Mickey43, I'm experiencing the same problem as you did when writing this post. Could you share how you fixed it? Thanks in advance

[Gabbo]

How big is the adBlue tank in the Superb?

[Shuggyboatsuperb]

6 hours ago, Gabbo said:

How big is the adBlue tank in the Superb?

In 2020 handbook it states “ about 13 litres”

 

On 08/12/2020 at 11:31, Guest said:

I think you need to add at least 10 litre before it registers.

Mine usually gets topped up with 3.5 litres when it asks for 0.75 gallon or 5 litres when asking for 0.75 - 1.25 gallon, and either of those register.

[Gabbo]

That's why I was asking because I normally the adBlue consumption on a car is pretty low so I didn't imagine a large tank so it should be more than capable to register 5L.

 

It should register almost any filling amount but unless you make a significant step in level the reading is heavily filtered to allow for gradient or inclination.

 

If you park on a level ground, it should recognise small amounts at least by the next start.

[Gabbo]

Is there a way to view the measured level of adBlue through the MIB3?

I haven't seen it but I'll look tomorrow.

 

Anyone know what kind of level sensor the tank has? 

 

Do you have any PCodes? 

I'd guess there are two obvious faults to check, a leak of the tank or a faulty level sensor

[Stonekeeper]

10 hours ago, Gabbo said:

How big is the adBlue tank in the Superb?

[Stonekeeper]

[Gabbo]

@Jonatan maybe worth to read the adBlue tank level in the driving data & then topup to see if the indicated level increases, then monitor over time to see if it rapidly decreases or doesn't change..

[Gabbo]

I tried this today.

I dont really understand what refill quantity min & max means but I'll monitor it over the next thousand kms next week

 

[Gammyleg]

On 02/12/2020 at 18:35, Mickey43 said:

Went and bought another 5 litres to try and reset it

Any idea why AdBlue systems are so dumb? Not just Skoda but all makes seem to have the problem of not registering partial refills. Fuel systems don't require a minimum fill-up so why should the AdBlue?

[Gabbo]

I think partially the legislation which defines very strict rules on how to apply limitations from low adBlue level once you've gone underneath the threshold to trigger the countdown.

 

I guess the system can see you have topped up small amounts but doesn't display this in terms of adBlue distance remaining unless you add enough to move outside of the warning region.

 

This is perhaps why you must add a minimum of 3L to deactivate the distance to "no start" warning.

 

[Jonatan]

On 04/02/2024 at 15:24, Gabbo said:

@Jonatan maybe worth to read the adBlue tank level in the driving data & then topup to see if the indicated level increases, then monitor over time to see if it rapidly decreases or doesn't change..

Sorry for late reply. I initially poured 5L in (and turned on ignition for 30sec before starting the car). Driving data didn't change and the car kept on warning about needing topping up on AdBlue. I then filled her up with an additional 5L (until full) and the car has still not registered the tank being filled. I will have to consult with a garage in the coming days.

[Gabbo]

@Jonatan any news from the garage as to the root cause?

 

[Gabbo]

Out of interest, what brand of AdBlue do you use to top-up?

I've noticed most big petrol stations now offer this from the pumps but you can also buy smaller 5L bottles from most places.

 

I'd prefer to top up myself than get charged a premium by the garage at each service.

[Jonatan]

@GabboSorry for late reply. Got my car from the garage this week. Diagnostics showed pressure too low somewhere in the AdBlue system. It turned out that the AdBlue line front AND back had frozen and needed replacing. Temperatures droppen to below 35 celsius here in northern Sweden, driving in these conditions likely caused this issue. Apparently a lot of VAG-cars have had this problem in these temperatures. The cost came at just over 12 000 SEK (~1100€). 

[Gabbo]

I'm surprised about this unless there is a known problem with the VW software.

 

Freezing of adBlue is known since the beginning of the technology.

Normally when you stop the car, the SCR system will purge the AdBlue from the system sucking it back into the tank to make sure the lines are clear and there's no chance of freezing.

The tank has a heating system which is activated when cold temperatures are suspected to ensure the AdBlue is fully thawed before activating the injection.

 

It's strange that frozen scr lines would prevent the tank from recognising you had added additional fluid unless the car was very cold at the time??