55 Plate VW Golf. ESP light staying on?

I have the same problem with my ESP light staying on all of the time. Been to my local VW dealership ( were I bought the car ) to book in for a full diagnostic, at a cost of £48.00. The service / receptionist guy said he did not know what the problem could be, and advised that he didn't want to guess. Whilst the guy in the parts dept advised my wife that they had been having alot of customers return with trouble with the ABS pumps, which appear to be the reason behind the fault, and advised that they have been doing the repair free of charge as a goodwill guesture. When I confronted the service guy with this info, he started to stammer, and advised that they would only be able to give me an accuate answer after completing the diagnostic. I decided to leave it at that, but wish that I had seen this fourum first.