Adblue system fault No restart in 650 miles

[Neik5]

Hi all,
After a bit of advice please.
I have a 2015 ultra which has 30k miles on it.
The car was bought used from Audi as approved used in Nov 17 so its 1 month out of warranty.

Came to the car yesterday an upon starting it came up with the message Adblue system fault, no restart in 650 miles.

I know there is plenty of adblue in as it was only filled (by Audi) in August and I’ve since topped it right up to see if that cleared the fault, and run it for 30 or so miles to see if it would recalibrate and clear the error message - no joy.

It has been on a diagnostic at an independent garage as Audi couldn’t fit me in straight away but there are no fault codes showing at all? The garage suggested the float may be stuck in the tank? Does anyone have any experience of this? Can it be fixed or is it a new tank?
I presume the diagnostic would show up if it was the pump or nox sensor, I’m a bit stuck how to proceed as new tanks are very expensive - £500+

Should I be ringing Audi and trying to get them to cover it as it’s only just out of warranty? Anyone had any success with this?

Any advice greatly appreciated
Many thanks

Neil

[A6S]

I would try and get them to cover it. What’s the worse can happen they say no.
Adblue can easily crystallise, if you spilt any on your drive you see it turns white quite quickly. Other thing is it could be a bit of frost stopping the float from going up.
It should have given you the 1000 or 1500 miles warning before the 650. Unfortunately it didn’t let you start if it thinks it zero.
Suppose only good thing is if it’s full and the float is stuck half way it’s never gonna go down far enough to show zero to stop you from starting. It’s an optimistic view
Try filling some more in it and see what happens. Could be a leak somewhere

[KevTrem]

If you have a search in the C7 section you'll see i had the same warning a couple of months ago that turned out to be the pump that failed. I had a look at the old pump that came out and its a complicated bit of kit. The garage said the part was approx £600 but I didn't pay a penny as I'd only had the car a couple of months.
If its not throwing up a fault code it may just need a recalibration, hopefully its just that.

[Whippy53]

Adblue System Fault - No Restart 1000km

[Neik5]

Update:
So after around 100 miles driving the car over the weekend (after the adblue tank was brimmed) I come to it this morning and no warning lights, no message and it seems the problem has cleared itself.
Quick call to the Indy garage to let them know and guy said he’d been thinking about it over the weekend and can only put it down to the float being stuck or the adblue crystallising around the float that caused the problem. Once it was filled up the float freed up and the system needed a few miles to recalibrate.
I’m taking this one as a win!
Just wanted to update so anyone else facing the same problem can give this a try before going to a dealer. You just need to be brave to drive it for 100 or so miles with the message saying no restart if it gets to zero.

Cheers for the reply’s, fingers crossed it’s fixed!

Neil

[A6S]

Good job
Nothing better than a free fix

[cooljasy]

Anyone had any luck getting dealer to compensate?

[darrenparker222]

hi guys
i did experience adblue malfunction as well, my mechanic did change nox sensor and errors went way you can check this blog it is about nox faults P229F62, P229E and P2202 NOx Sensor Error Codes Explained - Xenons4U Automotive Blogs

[FrugalShaun]

This has just happened to me with my 2015 A6 estate. I was driving home from Paris and got the warning that says "No restart after 650 miles". No error code. There was also a general engine warning light.

Normally, whenever adblue is low, it warns me at 2,000 miles. I knew something was wrong because I'd only recently topped it up. Anyway, I stopped at a service station and added 5 litres of adblue. The warning remained on. I then had to drive the ~500miles back to Manchester and the warning remain on the entire time.

The current situation is that the car is saying "No restart after 150 miles". I've called my local Audi and left a message. Hoping someone calls me back so I can get it booked in. It's not under warranty so I'm expecting to get rinsed!

I'm nervous about trying a local garage but if it is as simple as a stuck float, they may be able to sort it, so will give them a try too. If anyone has any other advice then please share.

Many thanks,

Shaun

[danclyon]

I had this on my 2015 as well - just after it had been in for MOT and service. They had it back for a day and only charged me the diagnostic fee. When I asked what was wrong, they said there was a software update that should have been applied to the car back in 2018 which corrects a fault with the adblue metering system and that was what was needed. No additional charge over the diagnostics....worth asking, but, sadly I couldn't get any more information out of the dealer despite asking for the TSB number etc. etc. so can't tell you anything more than that....