I'm another victim of the servo fault. First time I had the message on the dash was approx. a month ago and because it said its fine to drive I`ve ignored it. It would be intermittent for weeks until this week when it would stay on all the time. I`ve done over 200 miles since the issue appeared for the first time.
I'm really glad I found this forum, otherwise I wouldn't have thought much of the issue as it said it is ok to drive... I really got worried yesterday when I read stories of faulty ABS.
Luckily for me I have 7 days of the Audi approved used warranty left so as many people here suggested I`ve phoned the Audi roadside assistance.
They didn't have any Audi technicians available today but they asked me if I want the AA or the VW technician to come out. I`ve asked for the VW technician and he was at mine within 1 hour.
When I said what the message on the dash says he knew straight away what the problem is, even before he spoke to me he said he knew it will be the servo sensor. He didn`t have any spare ones but he said he will phone the local Audi service and will ask them if they have any in stock, but highlighted that if they don't, I should not be driving the car.
Luckily they had a few in stock so he went to get it and was back within 30min. Took him 1 minute to replace it and 15min to record it on their system and the job was done.
Im so happy that even though I drove the car for a few weeks with the faulty servo sensor it didn`t cause damage to the ABS unit. Of course the technician confirmed that all models form the VAG group so VW, AUDI, SKODA etc. that use this sensor have the same issue and he has seen a lot of cars where it caused damage to the ABS.
