It ensures the ABS and ESP modulates appropriately for the size of brakes. Probably not much in it but uf VW went to the trouble of having different settings it must matter.Just reading this thread again. Two questions popped into my mind.
Firstly, what difference to the van does making the changes @mmi posted on #38 make. Is there a negative to not making the changes? @Pauly
Secondly, what happens if you installed even bigger discs than the 340mm? What would have to be done with coding then?
If you go even bigger there's nithing you can do though it would be wise to code for 340mm if you go from 308 to a BBK