A little bird once told me that on certain Fords up to a model year, the diagnostic connector isn't actually attached to the ECU, to prevent 'enthusiasts' from fixing the problem themselves. I bought a gunson code reader for my K plate twincam Sierra, but it doesn't blink at all and the engine behaves perfectly normally whether its connected or not, so there may be some element of truth in that.

Or I just got a duff Gunson.

I found a page ages ago that had some interesting facts on the L8, including a brief pin layout - I don't know how relevant to your P8 it is though Here's a link:

http://www.ludd.luth.se/~rotax/weber.../iaw_conn.html