There is though, depending how the car was sold e.g as described with Warranty, the warranty doc that was signed could very well be with warranty provider so the contract is between them, not the seller as the car as as described. Similar to an insurance broker. The consumer rights are very broad with terms such as 'satisfactory quality' at the time of sale of a trader. All sorts of grey areas, for example satisfactory quality also takes into account the cars age, especially with electronics. I have been to court a few times. (As independent engineer with electronics, not my cases) and seen some people really shafted.
I'm not doubting you for a second - I'm extremely interested to see where this applies exactly in the law as I can use this myself. Can you point me to any legal docs please? There are two cases currently on the go I'm involved with directly.