Danboy1973 et al,
I got through to Motor Ombudsman (who Audi UK suggested to contact), however as you've found, when they hear the car is out of warranty, that is an immediate dismissal. They did tell me to contact the DVLA (he meant DVSA) if I thought it was a safety issue. I had already started this last week (around 10th Sep) and have had two emails since. The last one was to say that an engineer is looking into this matter and will review it within a month (patience required and a lot of hassle at home/work etc.). I doubt things will move quickly, although I'm sure Audi UK will be totally open and candid when contacted!
This 'admission' may be of interest to all - this came via email to me from our only NI approved Audi dealer (emphasis mine):-
"The current fault in the vehicle has caused a fault within the ABS system which has permanently deactivated the ABS brake control unit."
Make what you want of this, but at least Audi are saying one fault (brake sensor) has caused the other fault (ABS fault). I'm not a lawyer, but surely that is an admission that Audi have dropped a clanger - why aren't they doing something for their customers (soon to be ex-customers)? I don't know how it works, but perhaps they need someone like the DVSA to force them into a recall, to allow them to claim some sort of insurance for the recall - anyone know?
This same dealer, could not provide details of how many cases Audi UK now has on record. To be fair my local dealer has offered me a reduction of £200 on the repair bill - still unfortunately too expensive for me. I didn't buy new from them, so they I guess don't have to offer goodwill - although of course a dealer with some sort of moral fibre would rightly fight for an owner, win a new customer and garner some positive publicity, which would more than pay for a repair bill like this!
Anyway, all, as mentioned before, don't hold back pushing, unless you don't mind forking out for Audi's mistake - please get in contact with DVSA.
Please find further information at: https://www.gov.uk/vehicle-recalls-and-faults/report-a-serious-safety-defect
Regards,
Andrew.