There's an electrical circuit runing to a connector in my sump, does anyone know what this is for? I assume it's a heating mechnism for the witnter months?

Or is it a thermocouple, that can be read through VAGCOm?

Alas, they're only golden, not crystal, so I can't be certain what variant and engine you have, but some Skodas have one or both of oil condition and oil level sensors fitted.

Sorry, it's an ASZ, 1.9...........

I'd reckon that this is the oil level monitoring system.

oil level

Yes, its an oil level sensor. Ensures you have a reasonable level of oil in the sump. Should you crack the sump, or similar you will get a warning light and BEEEEP to warn you to bloody stop and turn the engine off before any damage is done.