Modern Vespa

Okay so I did do some searching on forum but didn't find much. Is there supposed to be something connected to the temp sensor on the engine, mine is just naked and I have some mystery wires. Also fan doesn't seems to be kicking in so would this be related? drives fine around town without overheating but GTV doesn't have temp gauge so hard to tell if everything is working like it should. All fluids are fine as well, recently changed.

One of my least favorite things about my 2007 GTV is the absence of a temp gauge. I'd like to know before the dummy light comes on...if it comes on at all. In your case, wouldn't you assume that if those temp sensor wires aren't hooked up to anything your dummy light may not even come on if you overheat?

Yeah that's one of my worries as I don't really push the bike on long journeys. The fan never kicks on no matter how long i got for and it doesn't seem to overheat to the point of cutoff so im a bit stumped really. Just want to make sure all is working as it should.

According to the wiring diagram,
https://manuals.wotmeworry.org.uk/Vespa/GTV125/
there are two separate thermal switches - one presumably on the engine for the over-temperature light, and another somewhere for the fan. On the GT125/200 this was in the cooling circuit up front by the radiator, but IDK where it might be for the GTV. The workshop manual may give a clue...

I had the same problem when I recently flushed my coolant. Like you said, I wanted to verify the fan would come on when it got up to temp. I tried letting the motor run for over 15 mins and the fan never kicked on. I wound up having to to run it hard up/down hills in my neighborhood to get the motor hot enough for the fan to come on. I was relieved when I finally heard it.