Thanks for the reply.
Yes I only get the Error 3 come up when the throttle sensor block is disconnected and it goes away when plugged back in.
The book is very specific with regard process. As in pgm card out and kill switch to off. Then throttle sensor disconnected, followed by pgm card back in and kill switch on. Then reverse for when plugging back in.
So I'm wondering if I'm missing something too. I'll contact my local Honda dealer to see if they have this special connection to test the servo, solenoid and throttle sensor wiring.