Electric fan still run off temp sensor?

So I just got my 94 xj and it's already got some work into it. It has an electric fan that looks factory but not positive. The electric fan is wire to a switch to turn it on, and it also turns on when running the air conditioning. My question is, with it being tied to a switch, will it still run off of engine temp if the engine gets too hot? There is an electrical connector towards the front of the engine that looks like it's connected to a temp sensor. I don't really see the point of it being ran to a switch if it runs automatically when the temp gets to high, maybe someone can enlighten me.

If it comes on with the AC then it should come on from temperature control as well, since the ECM controls the ground. Most hardwired switches are just secondary ground wires so you can force the circuit on whenever you want. Useful when winching, wheeling on hot days, etc., so you can keep radiator temps under control. The built-in temperature switch is in the range of 215-220, and at the point its starting to get hard to shed heat, so turning it on before then helps to keep the temperature down

Oh okay, it's just so you can manually turn on the fan since the ecm doesn't kick the fan on at a low enough temp for low speed/air flow. Makes sense