In a word, logistics. By and large, VW cars are not standalone, but part of modular systems, with the largest system based on the Golf platform. It makes sense to stop production of the older style parts (accounting for numbers that their modelling calculates are required to be kept for spares) as early as possible and start putting newer parts into all common-platform vehicles as part of the platform transition as it simplifies their supply chain. Presumably VW's engineering has developed to such a point that while the wires remain the same, the major components can change without difficultly, as long as they are all designed to work with the new communications protocol. I have no idea what has happened in the move from the MkVI to the MkVII (as I have no impetus to do the research), but the protocol changed from DDP to BAP in the move to the MkVI. The RNS-510 has a bit that can be changed in VCDS so it can be used in cars based on either protocol, but perhaps the new head units don't, or Ross Tech haven't yet exposed that bit in their ongoing reverse-engineering efforts.Quote:
Originally Posted by tigger73
