OK,

 

I've found the wires you mentioned. They are a twisted pair and run from the Nav control module to the touchscreen.

 

I can't see, from the diagram, why these should cause problems.

 

Are they located in the correct terminals Phil?

 

NCM- Yellow CA257-7 goes to Touchscreen FC92-4

 

NCM - Blue  CA257-20 goes to Touchscreen FC92-15

Having given this more thought, if the wiring was CANbus and misconnected, it would drag the bus down, probably causing comms failure Phil.

 

First thing I'd check then is that the wires are connected as per my previous post.

Fitted CDC in my S-Type today,had to enable the cdc for the car's system to recognise it via my Mongoose cable.A satisfactory outcome and very happy.I am even happier since it cost under £30 off the bay included cassette and free shipping. :D