Many thanks for the reply.
I've got the TIM unit but have no idea how to use it other than your directions, and with my very limited knowledge and no disc that seems a dead end.
Found something about just using a length of wire to reset the SRS from a Honda forum. A vague memory of my own 827 and an ABS problem was solved with a paper clip.
The T4 users manual calls for connectors DTC4007A & DTC0061A for the 800, and I'm not even sure I've got either of those, or if my connectors in the attic are labelled.
The length of wire sounds like the best option
Thanks again
ps. Just checked. I do indeed have the DTC0061A (blue connector) but my longer one is DTC4007B not A