My hands are obviously to big, I took off the nearside wheel and pulled back the wheelarch liner on the one I did a few weeks ago.
This one had developed a leak and filled the connector with coolant, corroding things up somewhat. I washed it with brake cleaner and put some "Electrolube contact lubricant" on it, available from RS Components, worked ok after but I did put a caveat on the invoice that the plug may need replacement in the future, just in case.
Shaun.