I've had these faults as "intermittent" vie OBD-eleven ever since I got the van. The "All-in Warranty" ran out last year and VW never did anything about these when I asked, apparently because they were only intermittent faults. I think it "might" have had a software update with them.Further to the above, I collected the van from VW Swindon yesterday (another 1009 mile round trip!). All they had really addressed was the amber 'check engine' light as caused by the two faults that I mentioned at Post #12 above:
-Reductant System Performance Bank 1.-SCR Nox Catalyst Efficiency Below Threshold Bank 1.
Just had an AdBlue nightmare that I thought I would share to maintain fellow members' anxiety levels
My van (T6) has had weird AdBlue issues more or less since purchased 2nd hand from Leicester VW (avoid!); AdBlue remaining distance randomly dropping from multiple 000's of miles to <600 miles to no start. Then it would clear itself after a bit of driving and jump up to multiple 000's of miles to go again (without top up).
So I had got used to this issue just sorting itself out... until last week while up in the NW highlands despite topping the AdBlue tank up before travelling c. 400 miles (realised i *may* have overfilled by mistake), the "XXX miles AdBlue remaining" never cleared, slowly declining to 80 (still nearly 400 miles from home). Having read on here that over-filling could be a problem I decanted some, to no effect. So I decided to cut my trip short and drive back in 1 go without stopping the engine. When I got home and parked up, the van did as promised and refused to start again.
I haven't had a chance to get it in to the local garage (trusted and fair priced, but not sure if all that technical with these systems), but today thought I would pop out and fiddle about with ODB-eleven. I tried the "SCR calibration" trick or whatever it's called which didn't seem to do anything. But while I was sat with the key in the ignition the red AdBlue warning (0 miles, no start) suddenly disappeared and was replace with the orange symbol and 35 miles to go. So at least this will let me drive it to the garage to get checked out!
I don't know the moral of this story, yet, but I have a feeling it will be expensive.

