to EJG, Hi,
If yours is an import from Japan the following will be relevant and of some help in understanding , if not you can ignore it. 🙂
My S-type is imported from Japan and I can tell you you that the wiring in the boot is not standard, it has wiring for CD changer and Sat Nav(which are functioning) but not normal Voice unit or Phone/blue tooth wiring in the harness. I am trying to devise my own bit of wiring to enable such devices to be fitted.
Regards