XJRider.com

So there I am, hoping to get my new (1997) XJ600S warm for an oil change, and hit the starter. Up to now, it's started almost before I hit it, very sweet. This time, it cranked for a moment but no go. Then, nothing. The neutral light and the red oil light. The starter solenoid didn't click, just one of the other relays behind the right hand cover.

Knowing there are some favourite culprits and wanting to get it properly healthy for the future, not just for right now, I:
- Replaced the starter solenoid, and its little and grotty blue and white wire
- Took off and rebuilt the starter, checking the brushes and the internals with a multimeter
- Cleaned loads of possibly relevant connecting blocks
- Got it to crank, by shorting the solenoid
- Suspect gremlins in the other ignition-related wiring
- Checked the clutch lever sensor with a meter
- Checked the side stand lever sensor... hang on, its two black wires lead up to a connector... that's not connected to anything. And no sign of anything to connect it to. Surely there should be a matching connector to plug into, and if that's been removed, it would never have run in the first place?

Getting a bit bored of the red oil light, not remotely electrically-minded, any ideas what else might have given up the ghost?
Thanks!