hello urban panzer, I came across a really useful post of yours regarding how to try and keep steering wheel remote and cd changer controls when fitting a new headunit on a discovery 2 . Best of all was the wirring diagram for the ISO and mini IIso blocks. I have bought a PC99 sony patch lead for my steering controls. I have cut off the wee connection block at one end and am going to slpice two of wires red and white to pins 2 and 3 of the grey block ISO , What is the 3rd black wire supposed to go to ??? Thanks for your help